UNI EN 15316-4-1_2008

NORMAEUROPEA Pagina I UNI EN 15316-4-1:2008 © UNI Riproduzione vietata. Tutti i diritti sono riservati. Nessuna parte del presente documento può essere riprodotta o diffusa con un mezzo qualsiasi, fotocopie, microfilm o altro, senza il consenso scritto dell’UNI. www.uni.com UNI Ente Nazionale Italiano di Unificazione Via Sannio, 2 20137 Milano, Italia UNI EN 15316-4-1 SETTEMBRE 2008 Impianti di riscaldamento degli edifici Metodo per il calcolo dei requisiti energetici e dei rendimenti dell’impianto Parte 4-1: Sistemi di generazione per il riscaldamento degli ambienti, sistemi a combustione (caldaie) Heating systems in buildings Method for calculation of system energy requirements and system efficiencies Part 4-1: Space heating generation systems, combustion systems (boilers) La norma è parte di una serie di norme sul metodo di calcolo dei requisiti energetici e dei rendimenti degli impianti di riscaldamento e di produzione di acqua calda sanitaria. La norma definisce i dati di ingresso richiesti, il metodo di calcolo e i dati in uscita per i sistemi di generazione del calore a combu- stione (caldaie) inclusi i relativi sistemi di controllo. La norma si applica anche ai casi di generazione combinata di riscaldamento e acqua calda sanitaria. Il caso di sola produzione di acqua calda sanitaria è trattato nella UNI EN 15316-3-3. TESTO INGLESE La presente norma è la versione ufficiale in lingua inglese della norma europea EN 15316-4-1 (edizione maggio 2008). ICS 91.140.10 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) © UNI Pagina II UNI EN 15316-4-1:2008 Le norme UNI sono elaborate cercando di tenere conto dei punti di vista di tutte le parti interessate e di conciliare ogni aspetto conflittuale, per rappresentare il reale stato dell’arte della materia ed il necessario grado di consenso. Chiunque ritenesse, a seguito dell’applicazione di questa norma, di poter fornire sug- gerimenti per un suo miglioramento o per un suo adeguamento ad uno stato dell’arte in evoluzione è pregato di inviare i propri contributi all’UNI, Ente Nazionale Italiano di Unificazione, che li terrà in considerazione per l’eventuale revisione della norma stessa. Le norme UNI sono revisionate, quando necessario, con la pubblicazione di nuove edizioni o di aggiornamenti. È importante pertanto che gli utilizzatori delle stesse si accertino di essere in possesso dell’ultima edizione e degli eventuali aggiornamenti. Si invitano inoltre gli utilizzatori a verificare l’esistenza di norme UNI corrispondenti alle norme EN o ISO ove citate nei riferimenti normativi. PREMESSA NAZIONALE La presente norma costituisce il recepimento, in lingua inglese, del- la norma europea EN 15316-4-1 (edizione maggio 2008), che assu- me così lo status di norma nazionale italiana. La presente norma è stata elaborata sotto la competenza dell’ente federato all’UNI CTI - Comitato Termotecnico Italiano La presente norma è stata ratificata dal Presidente dell’UNI ed è entrata a far parte del corpo normativo nazionale il 25 settembre 2008. Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 15316-4-1 May 2008 ICS 91.140.10 English Version Heating systems in buildings - Method for calculation of system energy requirements and system efficiencies - Part 4-1: Space heating generation systems, combustion systems (boilers) Systèmes de chauffage dans les bâtiments - Méthode de calcul des besoins énergétiques et des rendements des systèmes - Partie 4-1 : Systèmes de génération de chauffage des locaux, systèmes de combustion (chaudières) Heizanlagen in Gebäuden - Berechnung und Bewertung der Energieeffizienz von Systemen - Teil 4-1: Wärmeerzeugung für die Raumheizung, Verbrennungssysteme This European Standard was approved by CEN on 11 April 2008. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMI TÉ EUROPÉEN DE NORMALI SATI ON EUROPÄI SCHES KOMI TEE FÜR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels © 2008 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 15316-4-1:2008: E UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 2 Contents Page Foreword..............................................................................................................................................................5 Introduction.........................................................................................................................................................7 1 Scope ......................................................................................................................................................8 2 Normative references............................................................................................................................8 3 Terms and definitions ...........................................................................................................................9 3.1 Definitions ..............................................................................................................................................9 3.2 Symbols and units...............................................................................................................................12 4 Principle of the method.......................................................................................................................14 4.1 Heat balance of the generation sub-system, including control of heat generation .....................14 4.1.1 Physical factors taken into account ..................................................................................................14 4.1.2 Calculation structure (input and output data) ..................................................................................14 4.2 Generation sub-system basic energy balance .................................................................................16 4.3 Auxiliary energy...................................................................................................................................17 4.4 Recoverable, recovered and unrecoverable system thermal losses .............................................17 4.5 Calculation steps .................................................................................................................................18 4.6 Multiple boilers or generation sub-systems .....................................................................................18 4.7 Using net or gross calorific values....................................................................................................19 4.8 Boundaries between distribution and generation sub-system.......................................................20 5 Generation sub-system calculation...................................................................................................22 5.1 Available methodologies ....................................................................................................................22 5.2 Seasonal boiler performance method based on system typology (typology method) ................22 5.2.1 Principle of the method.......................................................................................................................22 5.2.2 Calculation procedure.........................................................................................................................23 5.3 Case specific boiler efficiency method .............................................................................................24 5.3.1 Principle of the method.......................................................................................................................24 5.3.2 Input data to the method.....................................................................................................................24 5.3.3 Load of each boiler..............................................................................................................................25 5.3.4 Generators with double service (space heating and domestic hot water production) ................27 5.3.5 Generator thermal losses ...................................................................................................................28 5.3.6 Total auxiliary energy..........................................................................................................................30 5.3.7 Recoverable generation system thermal losses ..............................................................................31 5.3.8 Fuel input..............................................................................................................................................32 5.3.9 Operating temperature of the generator ...........................................................................................32 5.4 Boiler cycling method .........................................................................................................................33 5.4.1 Principle of the method.......................................................................................................................33 5.4.2 Load factor ...........................................................................................................................................36 5.4.3 Specific thermal losses.......................................................................................................................36 5.4.4 Total thermal losses............................................................................................................................39 5.4.5 Auxiliary energy...................................................................................................................................40 5.4.6 Calculation procedure for single stage generators .........................................................................41 5.4.7 Multistage and modulating generators .............................................................................................41 5.4.8 Condensing boilers .............................................................................................................................44 5.4.9 Systems with multiple generators .....................................................................................................48 Annex A (informative) Sample seasonal boiler performance method based on system typology (typology method) ..............................................................................................................50 A.1 Scope ....................................................................................................................................................50 A.2 Limitations in use of this method ......................................................................................................50 A.3 Boiler typologies definition ................................................................................................................50 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. 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EN 15316-4-1:2008 (E) 3 A.4 Procedure............................................................................................................................................. 51 A.5 Declaring values of seasonal efficiency........................................................................................... 55 Annex B (informative) Additional formulas and default values for parametering the case specific boiler efficiency method ...................................................................................................... 56 B.1 Information on the method................................................................................................................. 56 B.1.1 Basic assumptions and intended use............................................................................................... 56 B.1.2 Known approximations....................................................................................................................... 56 B.2 Polynomial interpolation formulas.................................................................................................... 56 B.3 Generator efficiencies and stand-by losses..................................................................................... 57 B.3.1 Default values for generator efficiency at full load and intermediate load as a function of the generator power output ............................................................................................................... 57 B.3.2 Stand-by heat losses .......................................................................................................................... 59 B.3.3 Correction factor taking into account variation of efficiency depending on generator average water temperature................................................................................................................. 60 B.4 Auxiliary energy .................................................................................................................................. 61 B.5 Recoverable generation thermal losses ........................................................................................... 62 B.5.1 Auxiliary energy .................................................................................................................................. 62 B.5.2 Generator envelope............................................................................................................................. 62 B.5.3 Default data according to boiler location ......................................................................................... 63 Annex C (informative) Default values for parametering the boiler cycling method................................ 64 C.1 Information on the method................................................................................................................. 64 C.1.1 Basic assumptions and intended use............................................................................................... 64 C.1.2 Known approximations....................................................................................................................... 64 C.2 Default specific losses........................................................................................................................ 64 C.2.1 Default data for calculation of thermal losses through the chimney with burner on .................. 64 C.2.2 Default values for calculation of thermal losses through the generator envelope...................... 65 C.2.3 Default values for calculation of thermal losses through the chimney with the burner off........ 66 C.3 Default values for calculation of auxiliary energy ........................................................................... 67 C.4 Additional default data for multistage and modulating burners .................................................... 68 C.5 Additional default data for condensing boilers ............................................................................... 69 Annex D (informative) General part default values and information........................................................ 71 D.1 Control factor....................................................................................................................................... 71 D.2 Intermediate load................................................................................................................................. 71 Annex E (informative) Calculation example for seasonal boiler performance method based on system typology.................................................................................................................................. 72 E.1 Introduction ......................................................................................................................................... 72 E.2 Input data ............................................................................................................................................. 72 E.3 Calculation procedure ........................................................................................................................ 73 E.4 Output data (connection to other parts of EN 15316)...................................................................... 74 Annex F (informative) Calculation examples for case specific boiler efficiency method ...................... 75 F.1 Condensing boiler example, data declared by the manufacturer .................................................. 75 F.1.1 Input data ............................................................................................................................................. 75 F.1.2 Calculation procedure ........................................................................................................................ 76 F.1.3 Output data (connection to other parts of EN 15316)...................................................................... 77 F.1.4 Conversion of net values to gross values........................................................................................ 77 F.2 Standard boiler example, default data .............................................................................................. 78 F.2.1 Input data ............................................................................................................................................. 78 F.2.2 Calculation procedure ........................................................................................................................ 79 F.2.3 Output data (connection to other parts of EN 15316)...................................................................... 81 Annex G (informative) Calculation examples for boiler cycling method .................................................. 82 G.1 Modulating condensing boiler ........................................................................................................... 82 G.1.1 Input data ............................................................................................................................................. 82 G.1.2 Calculation procedure ........................................................................................................................ 84 G.1.3 Output data (connection to other parts of EN 15316)...................................................................... 88 G.2 Standard, on-off atmospheric boiler ................................................................................................. 88 G.2.1 Input data ............................................................................................................................................. 88 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. 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EN 15316-4-1:2008 (E) 4 G.2.2 Calculation procedure.........................................................................................................................90 G.2.3 Output data (connection to other parts of EN 15316) ......................................................................91 Annex H (informative) Boiler water temperature calculation.....................................................................92 H.1 Boiler flow temperature and return temperature..............................................................................92 H.2 Boiler flow rate is the same as the distribution flow rate (no by-pass) .........................................93 H.3 Boiler flow rate is not the same as the distribution flow rate (by-pass connection or recirculation pump) .............................................................................................................................94 H.4 Parallel connection of boilers.............................................................................................................96 H.5 Boiler average water temperature......................................................................................................97 H.6 Example of water temperature calculation .......................................................................................98 Bibliography......................................................................................................................................................99 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 5 Foreword This document (EN 15316-4-1:2008) has been prepared by Technical Committee CEN/TC 228 “Heating systems in buildings”, the secretariat of which is held by DS. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2008, and conflicting national standards shall be withdrawn at the latest by November 2008. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association (Mandate M/343), and supports essential requirements of EU Directive 2002/91/EC on the energy performance of buildings (EPBD). It forms part of a series of standards aimed at European harmonisation of the methodology for calculation of the energy performance of buildings. An overview of the whole set of standards is given in CEN/TR 15615, ‘Explanation of the general relationship between various CEN standards and the Energy Performance of Buildings Directive (EPBD)’ ("Umbrella document").' The subjects covered by CEN/TC 228 are the following: - design of heating systems (water based, electrical, etc.); - installation of heating systems; - commissioning of heating systems; - instructions for operation, maintenance and use of heating systems; - methods for calculation of the design heat loss and heat loads; - methods for calculation of the energy performance of heating systems. Heating systems also include the effect of attached systems such as hot water production systems. All these standards are systems standards, i.e. they are based on requirements addressed to the system as a whole and not dealing with requirements to the products within the system. Where possible, reference is made to other European or International Standards, a.o. product standards. However, use of products complying with relevant product standards is no guarantee of compliance with the system requirements. The requirements are mainly expressed as functional requirements, i.e. requirements dealing with the function of the system and not specifying shape, material, dimensions or the like. The guidelines describe ways to meet the requirements, but other ways to fulfil the functional requirements might be used if fulfilment can be proved. Heating systems differ among the member countries due to climate, traditions and national regulations. In some cases requirements are given as classes so national or individual needs may be accommodated. In cases where the standards contradict with national regulations, the latter should be followed. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 6 EN 15316, Heating systems in buildings — Method for calculation of system energy requirements and system efficiencies consists of the following parts: Part 1: General Part 2-1: Space heating emission systems Part 2-3: Space heating distribution systems Part 3-1: Domestic hot water systems, characterisation of needs (tapping requirements) Part 3-2: Domestic hot water systems, distribution Part 3-3: Domestic hot water systems, generation Part 4-1: Space heating generation systems, combustion systems (boilers) Part 4-2: Space heating generation systems, heat pump systems Part 4-3: Heat generation systems, thermal solar systems Part 4-4: Heat generation systems, building-integrated cogeneration systems Part 4-5: Space heating generation systems, the performance and quality of district heating and large volume systems Part 4-6: Heat generation systems, photovoltaic systems Part 4-7: Space heating generation systems, biomass combustion systems According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 7 Introduction This European Standard presents methods for calculation of the additional energy requirements of a heat generation system in order to meet the distribution and/or storage sub-system demand. The calculation is based on the performance characteristics of the products given in product standards and on other characteristics required to evaluate the performance of the products as included in the system. This method can be used for the following applications:  judging compliance with regulations expressed in terms of energy targets;  optimisation of the energy performance of a planned heat generation system, by applying the method to several possible options;  assessing the effect of possible energy conservation measures on an existing heat generation system, by calculating the energy use with and without the energy conservation measure. The user shall refer to other European Standards or to national documents for input data and detailed calculation procedures not provided by this European Standard. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 8 1 Scope This European Standard is part of a series of standards on the method for calculation of system energy requirements and system efficiencies of space heating systems and domestic hot water systems. The scope of this specific part is to standardise the:  required inputs;  calculation method;  resulting outputs; for space heating generation by combustion sub-systems (boilers), including control. This European Standard is the general standard on generation by combustion sub-systems (boilers). If a combustion generation sub-system is within the scope of another specific part of the EN 15316 series (i.e. part 4.x), the latter shall be used. EXAMPLE Biomass combustion generation sub-systems are within the scope of prEN 15316-4-7. This European Standard is also intended for the case of generation for both domestic hot water production and space heating. The case of generation only for domestic hot water production is treated in EN 15316-3- 3. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 297, Gas-fired central heating boilers - Type B 11 and B 11Bs boilers fitted with atmospheric burners of nominal heat input not exceeding 70 kW EN 303-5, Heating boilers – Part 5: Heating boilers for solid fuels, hand and automatically stocked, nominal heat output of up to 300 kW - Terminology, requirements, testing and marking EN 304, Heating boilers — Test code for heating boilers for atomizing oil burners EN 656, Gas-fired central heating boilers — Type B boilers of nominal heat input exceeding 70 kW but not exceeding 300 kW EN 15034:2006, Heating boilers - Condensing heating boilers for fuel oil EN 15035, Heating boilers - Special requirements for oil fired room sealed units up to 70 kW EN 15316-2-1, Heating systems in buildings - Method for calculation of system energy requirements and system efficiencies – Part 2.1: Space heating emission systems EN 15316-2-3:2007, Heating systems in building - Method for calculation of system energy requirements and system efficiencies – Part 2.3: Space heating distribution systems UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. 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EN 15316-4-1:2008 (E) 9 EN 15316-3-2, Heating systems in buildings - Method for calculation of system energy requirements and system efficiencies – Part 3.2: Domestic hot water systems, distribution EN 15456, Heating boilers – Electrical power consumption for heat generators – System boundaries – Measurements EN 15603, Energy performance of buildings — Overall energy use and definition of energy ratings EN ISO 7345:1995, Thermal insulation - Physical quantities and definitions (ISO 7345:1987) EN ISO 13790, Thermal performance of buildings - Calculation of energy use for space heating (ISO 13790:2004) 3 Terms and definitions 3.1 Definitions For the purposes of this document, the terms and definitions given in EN ISO 7345:1995 and the following apply. 3.1.1 space heating process of heat supply for thermal comfort 3.1.2 domestic hot water heating process of heat supply to raise the temperature of the cold water to the intended delivery temperature 3.1.3 heated space room or enclosure which for the purposes of the calculation is assumed to be heated to a given set-point temperature or set-point temperatures 3.1.4 system thermal loss thermal loss from a technical building system for heating, cooling, domestic hot water, humidification, dehumidification, ventilation or lighting or other appliances that does not contribute to the useful output of the system NOTE Thermal energy recovered directly in the sub-system is not considered as a system thermal loss but as heat recovery and is directly treated in the related system standard. 3.1.5 auxiliary energy electrical energy used by technical building systems for heating, cooling, ventilation and/or domestic hot water to support energy transformation to satisfy energy needs NOTE 1 This includes energy for fans, pumps, electronics, etc. NOTE 2 In EN ISO 9488 [4], the energy used for pumps and valves is called "parasitic energy". 3.1.6 heat recovery heat generated by a technical building system or linked to a building use (e.g. domestic hot water) which is utilised directly in the related system to lower the heat input and which would otherwise be wasted (e.g. preheating of the combustion air by flue gas heat exchanger) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. 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EN 15316-4-1:2008 (E) 10 3.1.7 total system thermal loss total of the technical system thermal loss, including recoverable system thermal losses 3.1.8 recoverable system thermal loss part of the system thermal loss which can be recovered to lower either the energy need for heating or cooling or the energy use of the heating or cooling system 3.1.9 recovered system thermal loss part of the recoverable system thermal loss which has been recovered to lower either the energy need for heating or cooling or the required energy use of the heating or cooling system 3.1.10 gross calorific value quantity of heat released by a unit quantity of fuel, when it is burned completely with oxygen at a constant pressure equal to 101 320 Pa, and when the products of combustion are returned to ambient temperature NOTE 1 This quantity includes the latent heat of condensation of any water vapour contained in the fuel and of the water vapour formed by the combustion of any hydrogen contained in the fuel. NOTE 2 According to ISO 13602-2 [5], the gross calorific value is preferred to the net calorific value. NOTE 3 The net calorific value does not take into account the latent heat of condensation. 3.1.11 net calorific value gross calorific value minus latent heat of condensation of the water vapour in the products of combustion at ambient temperature 3.1.12 calculation step discrete time interval for the calculation of the energy needs and uses NOTE Typical discrete time intervals are one hour, one month or one heating and/or cooling season, operating modes, and bins. 3.1.13 calculation period period of time over which the calculation is performed NOTE The calculation period can be divided into a number of calculation steps. 3.1.14 external temperature temperature of external air NOTE 1 For transmission heat transfer calculations, the radiant temperature of the external environment is supposedly equal to the external air temperature; long-wave transmission to the sky is calculated separately. NOTE 2 The measurement of external air temperature is defined in EN ISO 15927-1, Hygrothermal performance of buildings - Calculation and presentation of climatic data — Part 1: Monthly means of single meteorological elements. 3.1.15 heat transfer coefficient factor of proportionality of heat flow governed by a temperature difference between two environments UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 11 3.1.16 boiler gas, liquid or solid fuelled appliance designed to provide hot water for space heating. It may (but need not) be designed to provide domestic hot water heating as well 3.1.17 combustion power product of the fuel flow rate and the net calorific power of the fuel 3.1.18 low temperature boiler non-condensing boiler designed as a low temperature boiler and tested as a low temperature boiler as prescribed by the Council Directive 92/42/EEC about Boiler Efficiency [1] 3.1.19 condensing boiler boiler designed to make use of the latent heat released by condensation of water vapour in the combustion flue products. The boiler must allow the condensate to leave the heat exchanger in liquid form by way of a condensate drain NOTE Boilers not so designed, or without the means to remove the condensate in liquid form, are called ‘non- condensing’. 3.1.20 oil condensing boiler boiler designed to make use of the latent heat released by condensation of water vapour in the combustion flue products of a liquid fuel [EN 15034:2006] 3.1.21 modes of operation various modes in which the heating system can operate EXAMPLES Set-point mode, cut-off mode, reduced mode, set-back mode, boost mode. 3.1.22 on/off boiler boiler without the capability to vary the fuel burning rate whilst maintaining continuous burner firing. This includes boilers with alternative burning rates set once only at the time of installation, referred to as range rating 3.1.23 multistage boiler boiler with the capability to vary the fuel burning rate stepwise whilst maintaining continuous burner firing 3.1.24 modulating boiler boiler with the capability to vary continuously (from a set minimum to a set maximum) the fuel burning rate whilst maintaining continuous burner firing UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 12 3.2 Symbols and units For the purposes of this document, the following symbols and units (Table 1) and indices (Table 2) apply. Table 1 – Symbols and units Symbol Name of quantity Unit b temperature reduction factor - c coefficient various c specific heat capacity J/kg·K or Wh/kg·K a) d thickness mm E energy in general (except quantity of heat, mechanical work and auxiliary (electrical) energy) J or Wh a) e expenditure factor - f factor - H calorific value J/mass unit or Wh/mass unit b) H heat transfer coefficient W/K k factor - m mass kg n exponent - N number of items Integer P power in general including electrical power W Q quantity of heat J or Wh a) t time, period of time s or h a) V volume L V' volume flow m³/s or m³/h a) W auxiliary (electrical) energy, mechanical work J or Wh a) x relative humidity % X volume fraction % loss factor % load factor - prefix for difference η efficiency factor % UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 13 Table 1 – Symbols and units Symbol Name of quantity Unit θ Celsius temperature °C density kg/m³ heat flow rate, thermal power W a) If seconds (s) is used as the unit of time, the unit for energy shall be J. If hours (h) is used as the unit of time, the unit for energy shall be Wh. b) Mass unit for fuel may be Stm³, Nm³ or kg. Table 2 – Indices add additional gnr generator plt pilot air air grs gross pmp after the combustion chamber aux auxiliary H heating Pn at nominal load avg average i, j, k indices Px at x load br before generator in input to sub-system r return brm boiler room ins insulation rbl recoverable ch chimney lat latent ref reference ci calculation step ls losses rvd recovered cmb combustion m mean s gross (calorific value) cond condensing max maximum sat saturation corr corrected / correction mass massic sby in stand-by operation ctr control min minimum st stoichiometric dis distribution n nominal sto storage dry dry gases net net test test conditions em emission O2 oxygen th thermal emr emitter off off W heating system water f flow (temperature) on on w water fg flue gas out output from sub- system wfg water to flue gas ge generator envelope P0 at zero load z indices gen generation sub- system Pint at intermediate load UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 14 Table 2 – Indices The indices specifying symbols for sub-system energy balance quantities are in the following order:  the first index represents the use (H = space heating, W = domestic hot water, etc.);  the second index represents the sub-system (gen = generation, dis = distribution, etc.);  the third index represents the balance item (ls = losses, in = input, aux = auxiliary, etc.). Other indices may follow for more details (rvd = recovered, rbl = recoverable, etc.). 4 Principle of the method 4.1 Heat balance of the generation sub-system, including control of heat generation 4.1.1 Physical factors taken into account The calculation method of the generation sub-system takes into account heat losses and/or recovery due to the following physical factors:  heat losses to the chimney (or flue gas exhaust) during total time of generator operation (running and stand-by);  heat losses through the generator(s) envelope during total time of generator operation (running and stand-by);  auxiliary energy. The relevance of these effects on the energy requirements depends on:  type of heat generator(s);  location of heat generator(s);  part load ratio;  operating conditions (temperature, control, etc.);  control strategy (on/off, multistage, modulating, cascading, etc.). 4.1.2 Calculation structure (input and output data) The calculation method of this standard shall be based on the following input data from other parts of the EN 15316-X-X series of standards:  heat demand of the distribution sub-system(s) for space heating ΣQ H,dis,in , calculated according to EN15316-2-3;  heat demand of the distribution sub-system(s) for domestic hot water ΣQ W,dis,in , calculated according to EN 15316-3-2, where appropriate. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 15 The performance of the generation sub-system may be characterised by additional input data to take into account:  type and characteristics of the generation sub-system;  generator settings;  type of the generation control system;  location of the generator;  operating conditions;  heat requirement. Based on these data, the following output data are calculated by this standard:  fuel heat requirement, E H,gen,in ;  total generation thermal losses (flue gas and generator envelope), Q H,gen,ls ;  recoverable generation thermal losses, Q H,gen,ls,rbl ;  generation auxiliary energy, W H,gen,aux . Figure 1 shows the calculation inputs and outputs of the generation sub-system. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 16 Key SUB Generation sub-system balance boundary HF Heating fluid balance boundary (see equation (1)) QH,gen,out Generation sub-system heat output (input to distribution sub-system(s)) EH,gen,in Generation sub-system fuel input (energyware) WH,gen,aux Generation sub-system total auxiliary energy QH,gen,aux,rvd Generation sub-system recovered auxiliary energy QH,gen,ls Generation sub-system total thermal losses QH,gen,ls,rbl Generation sub-system thermal loss recoverable for space heating QH,gen,ls,th,rbl Generation sub-system thermal loss (thermal part) recoverable for space heating QH,gen,aux,rbl Generation sub-system recoverable auxiliary energy QH,gen,ls,th,nrbl Generation sub-system thermal loss (thermal part) non recoverable QH,gen,aux,nrbl Generation sub-system non recoverable auxiliary energy NOTE Figures shown are sample percentages. Figure 1 – Generation sub-system inputs, outputs and energy balance 4.2 Generation sub-system basic energy balance The basic energy balance of the generation sub-system is given by ls gen, H, rvd aux, gen, H, out gen, H, in gen, H, Q Q Q E + − = (1) where E H,gen,in heat requirement of the generation sub-system (fuel input); Q H,gen,out heat supplied to the distribution sub-systems (space heating and domestic hot water); UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 17 Q H,gen,aux,rvd auxiliary energy recovered by the generation sub-system (i.e. pumps, burner fan, etc.); Q H,gen,ls total losses of the generation sub-system (through the chimney, generator envelope, etc.). NOTE QH,gen,ls takes into account flue gas and generator envelope losses, part of which may be recoverable according to location. See 4.4, 5.3.5 and 5.4.4. If there is only one generation sub-system _ _ + ⋅ = j j in, dis, W, i i in, dis, H, ctrl out gen, H, Q Q f Q (2) where f ctrl factor taking into account emission control losses. Default value of f ctrl is given in Table D.1. Other values may be specified in a national annex, provided that emission control losses has not been already taken into account in the emission part (EN 15316-2-1) or in the distribution part (EN 15316-2-3). If there are multiple generation sub-systems or multiple boilers, see 4.6, 5.3.3 and 5.4.9. If the generator provides heat for heating and domestic hot water, the index H shall be replaced by HW. In the following only H is used for simplicity. 4.3 Auxiliary energy Auxiliary energy is the energy, other than fuel, required for operation of the burner, the primary pump and any equipment whose operation is related to operation of the heat generation sub-system. Auxiliary energy is counted in the generation part as long as no transport energy from the auxiliary equipment is transferred to the distribution sub-system (example: zero–pressure distribution array). Such auxiliary equipment can be (but need not be) an integral part of the generator. Auxiliary energy, normally in the form of electrical energy, may be partially recovered as heat for space heating or for the generation sub-system. Examples of recoverable auxiliary energy:  electrical energy transmitted as heat to the water of the primary circuit;  part of the electrical energy for the burner fan. Example of non-recoverable auxiliary energy:  electrical energy for electric panel auxiliary circuits, if the generator is installed outside the heated space. 4.4 Recoverable, recovered and unrecoverable system thermal losses Not all of the calculated system thermal losses are necessarily lost. Some of the losses are recoverable and part of the recoverable system thermal losses are actually recovered. Example of recoverable system thermal losses are:  thermal losses through the envelope of a generator installed within the heated space. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 18 Examples of non-recoverable system thermal losses are:  thermal losses through the envelope of a generator installed outside the heated space;  thermal losses through the chimney installed outside the heated space. Recovery of system thermal losses to the heated space can be accounted for:  either as a reduction of total system thermal losses within the specific part (simplified method);  or, by taking into account recoverable system thermal losses as gains (holistic method) or as a reduction of the energy use according to EN 15603. This European Standard allows both approaches. Generation system thermal losses recovered by the generation sub-system are directly taken into account in the generation performance. EXAMPLE Combustion air preheating by flue gas losses. 4.5 Calculation steps The objective of the calculation is to determine the energy input of the heating generation sub-system for the entire calculation period (usually one year). This may be done in one of the following two different ways:  by using average (usually yearly) data for the entire calculation period;  by dividing the calculation period into a number of calculation steps (e.g. months, weeks, bins, operation modes as defined in EN ISO 13790) and perform the calculations for each step using step-dependent values and adding up the results for all the steps over the calculation period. NOTE Generation efficiency is strongly dependent on the load factor and this relationship is not linear. To achieve precision, the calculation steps should not be longer than 1 month. 4.6 Multiple boilers or generation sub-systems The primary scope of this European Standard is to calculate losses, fuel requirement and auxiliary energy requirements for an individual boiler. If there are multiple generation sub-systems, the general part allows for a modular approach to take into account cases where:  a heating system is split up in zones with several distribution sub-systems;  several heat generation sub-systems are available. EXAMPLE 1 A separate circuit may be used for domestic hot water production. EXAMPLE 2 A boiler may be used as a back-up for a solar and/or cogeneration sub-system(s). In these cases, the total heat requirement of the connected distribution sub-systems i Q X,dis,in,i shall equal the total heat output of the generation sub-systems i Q X,gen,out,j : _ _ = i i in, dis, X, j j out, gen, X, Q Q (3) NOTE X is used as an index in equation (3) to mean space heating, domestic hot water heating or other building services requiring heat from a generation sub-system. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 19 If there are several generation sub-systems, the total heat demand of the distribution sub-system(s) shall be distributed among the available generation sub-systems. The calculation described in 5.2, 5.3, 5.4 and/or other relevant parts of EN 15316-4 shall be performed independently for each heat generation device j, on the basis of Q H,gen,out,j . Criteria for distribution of the total heat demand among the available generation sub-systems may be based on physical, efficiency or economic considerations. EXAMPLE 3 Solar or heat pump sub-system maximum heat output. EXAMPLE 4 Heat pumps or cogeneration optimum (either economic or energetic) performance range. Appropriate criteria for specific types of generation sub-systems can be found in the relevant parts of the EN 15316-4-X series of standards. Procedures to split the load among multiple combustion generators (boilers) are given for basic cases in 5.3.3 and 5.4.9. EXAMPLE 5 Given QH,dis,in, the maximum output of a solar generation system QH,sol,out should be calculated first, and subsequently the heat output that can be provided by a cogeneration system is added Qchp,gen,out. The rest (QH,gen,out,boil = QH,dis,in - QH,sol,out - Qchp,gen,out, see Figure 2) is attributed to boilers and may be further split among multiple boilers according to 5.3.3 and 5.4.9. Figure 2 – Example of load splitting among generation sub-systems 4.7 Using net or gross calorific values Calculations described in 5 may be performed according to net or gross calorific values. All parameters and data shall be consistent with this option. If the calculation of the generation sub-system is performed according to data based on fuel net calorific values H i , total losses Q H,gen.ls,net , non recoverable thermal losses Q H,gen,ls,th,nrbl,net and generation sub-system energyware E H,gen,in,net (i.e. fuel input for combustion systems) based on net calorific values may be converted to values Q H,gen,ls,grs , Q H,gen,ls,th,nrbl,grs and E H,gen,in,grs based on gross calorific values H s by addition of the latent heat of condensation Q lat according to the following: i i s net in, gen, H, lat H H H E Q − ⋅ = (4) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 20 lat net in, gen, H, grs in, gen, H, Q E E + = (5) lat net ls, gen, H, grs ls, gen, H, Q Q Q + = (6) lat net nrbl, th, ls, gen, H, grs nrbl, th, ls, gen, H, Q Q Q + = (7) 4.8 Boundaries between distribution and generation sub-system Boundaries between generation sub-system and distribution sub-system should be defined according to the following principles. If the generation sub-system includes the generator only (i.e. there is no pump within the generator), the boundary with the distribution sub-system is represented by the hydraulic connection of the boiler, as shown in Figure 3. Key gen generation sub-system dis distribution sub-system em emission sub-system Figure 3 – Sample sub-systems boundaries A pump physically within the boiler is however considered part of the distribution sub-system if it contributes to the flow of heating medium to the emitters. An example is shown in Figure 4. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 21 Key gen generation sub-system dis distribution sub-system em emission sub-system Figure 4 – Sample sub-systems boundaries Only pumps dedicated to generator requirements may be considered within the generation sub-system. An example is shown in Figure 5. Key gen generation sub-system dis distribution sub-system em emission sub-system Figure 5 – Sample sub-systems boundaries UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 22 5 Generation sub-system calculation 5.1 Available methodologies In this standard, three performance calculation methods for the heat generation sub-system are described corresponding to different use (simplified or detailed estimation, on site measurements, etc.). The calculation methods differ with respect to:  required input data;  operating conditions taken into account;  calculation steps applied. For the first method (see 5.2), the considered calculation step is the heating season. The performance calculation is based on the data related to the Council Directive 92/42/EEC about Boiler Efficiency [1]. The operation conditions taken into account (climate, distribution sub-system connected to the generator, etc.) are approximated by typology of the considered region and are not case specific. If this method is to be applied, an appropriate national annex with the relevant values shall be available. The second method (see 5.3) is also based on the data related to the Council Directive 92/42/EEC about Boiler Efficiency [1], but supplementary data are needed in order to take into account the specific operation conditions of the individual installation. The considered calculation step can be the heating season but may also be a shorter period (month, week and/or the operation modes according to EN ISO 13790). The method is not limited and can be used with the default values given in informative Annex B. The third method (see 5.4) distinguishes in a more explicit way the losses of a generator which occurs during boiler cycling (i.e. combustion losses). Some of the parameters can be measured on site. This method is well adapted for existing buildings and to take into account condensation heat recovery according to operating conditions. The calculation method to be applied is chosen as a function of the available data and the objectives of the calculation. Further details on each method are given in the respective parametering informative Annexes (A, B and C). 5.2 Seasonal boiler performance method based on system typology (typology method) 5.2.1 Principle of the method This method assumes that  climatic conditions,  operation modes,  typical occupancy patterns of the relevant building sector, have been considered and are incorporated in a procedure to convert standard test results of boiler efficiency (as used for the Council Directive 92/42/EEC about Boiler Efficiency [1]) into a seasonal efficiency for the relevant building sector. The stages within the seasonal efficiency calculation procedure are: a) adapt test results for uniformity, taking account of boiler type, fuel and specific conditions for testing imposed by the Council Directive 92/42/EEC about Boiler Efficiency [1] and the relevant standards; UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 23 b) adjust for annual performance in installed conditions, taking account of regional climate, operation modes and occupancy patterns typical of the relevant building sector; c) perform the calculations and determine fuel heat requirement, total generation thermal loss (as an absolute value), recoverable generation thermal loss, auxiliary energy, recoverable auxiliary energy. The procedure allows for national characteristics of the relevant building sector. 5.2.2 Calculation procedure 5.2.2.1 Selection of appropriate seasonal efficiency procedure A seasonal efficiency calculation procedure is selected from the appropriate national annex on the basis of the following information:  region (climate) in which the building is situated;  building sector (housing, commercial, industrial, etc). The procedure shall include limitation in use, relevant boundary conditions and reference to validation data. The procedure shall be defined in a national annex. If there is no appropriate national annex, this method cannot be used. Annex A (informative) is an example of a seasonal efficiency calculation procedure, known as SEDB_UK, and it represents conditions in the housing sector of the UK. 5.2.2.2 Input information required for the seasonal efficiency procedure Input information for the procedure shall comprise:  heat demand of the distribution sub-system(s) for space heating ΣQ H,dis,in calculated according to EN15316-2-3;  heat demand of the distribution sub-system(s) for domestic hot water ΣQ W,dis,in calculated according to EN 15316-3-2, where appropriate. Input information for the procedure may comprise:  full-load and 30 % part-load efficiency test results produced in accordance with standard tests as required for the Council Directive 92/42/EEC about Boiler Efficiency [1];  boiler type (condensing or not, combination or not, hot water store included or not, etc);  fuel used (natural gas, LPG, oil, etc);  boiler power output (maximum and minimum if a range);  ignition method (permanent pilot flame or not);  burner type (modulating, multistage or on/off);  internal store included in efficiency tests (yes/no);  store characteristics (volume, insulation thickness). UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 24 5.2.2.3 Output information obtained from the seasonal efficiency procedure Output information from the procedure shall comprise:  E H,gen,in fuel heat requirement;  W H,gen,aux auxiliary energy;  Q H,gen,ls,rbl recoverable system thermal losses for space heating. 5.3 Case specific boiler efficiency method 5.3.1 Principle of the method This method is related to the Council Directive 92/42/EEC about Boiler Efficiency [1] and is based on the following principle: a) data are collected for three basic load factors or power outputs:  gnr,Pn efficiency at 100 % load;  gnr,Pint efficiency at intermediate load;  gnr,ls,P0 losses at 0 % load; b) efficiency and losses data are corrected according to boiler operating conditions (temperature); c) losses power at 100 % load gnr,ls,Pn and at intermediate load gnr,ls,Pint are calculated according to corrected efficiencies; d) calculation of losses power corresponding to the actual power output is made by linear or polynomial interpolation between losses powers for the three basic power outputs; NOTE For the case specific boiler efficiency method, all powers and the load factor gnr are referred to generation sub-system output. e) auxiliary energy is calculated taking into account the actual power output of the boiler; f) recoverable generator envelope thermal losses are calculated according to a tabulated fraction of stand- by heat losses and boiler location; g) recoverable auxiliary energy is added to recoverable generator envelope thermal losses to provide total recoverable thermal losses. 5.3.2 Input data to the method 5.3.2.1 Boiler data The boiler is characterised by the following values:  Pn generator output at full load;  gnr,Pn generator efficiency at full load;  gnr,w,test,Pn generator average water temperature at test conditions for full load; UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 25  f corr,Pn correction factor of full-load efficiency;  Pint generator output at intermediate load;  gnr,Pint generator efficiency at intermediate load;  gnr,w,test,Pint generator average water temperature at test conditions for intermediate load;  f corr,Pint correction factor of intermediate load efficiency;  gnr,ls,P0 stand-by heat loss at test temperature difference ∆ gnr,test,P0 ;  ∆θ gnr,test,P0 difference between mean boiler temperature and test room temperature at test conditions;  P aux,gnr,Pn power consumption of auxiliary devices at full load;  P aux,gnr,Pint power consumption of auxiliary devices at intermediate load;  P aux,gnr,P0 stand-by power consumption of auxiliary devices;  gnr,w,min minimum operating boiler temperature. Data to characterise the boiler shall be taken from one of the following sources, listed in priority order: a) product data from the manufacturer, if the boiler has been tested according to EN 297, EN 303-5, EN 304, EN 656, EN 15034, EN 15035 and/or EN 15456 (auxiliary power data); b) default data from the relevant national annex; c) default data from Annexes B or D. It shall be recorded whether or not the efficiency values include auxiliary energy recovery. 5.3.2.2 Actual operating conditions Actual operating conditions are characterised by the following values:  Q H,gen,out heat output to the heat distribution sub-system(s);  θ gnr,w,m average water temperature in the boiler;  θ gnr,w,r return water temperature to the boiler (for condensing boilers);  θ i,brm boiler room temperature;  b brm temperature reduction factor depending on the location of the generator. 5.3.3 Load of each boiler 5.3.3.1 Generation sub-system average power Generation sub-system average power H,gen,out is given by: gen out gen, H, out gen, H, t Q = (8) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 26 where t gen total time of generator(s) operation. 5.3.3.2 Single boiler generation sub-system If there is only one generator installed, the load factor gnr is given by: Pn out gen, H, gnr = (9) where Pn nominal power output of the generator. 5.3.3.3 Multiple boilers generation sub-system 5.3.3.3.1 General If there are several boilers installed, distribution of the load among boilers depends on control. Two types of control are distinguished:  without priority;  with priority. 5.3.3.3.2 Multiple generators without priority All generators are running at the same time and therefore the load factor gnr is the same for all boilers and is given by: _ = i i Pn, out gen, H, gnr (10) where Pn,i nominal power output of generator i at full load. 5.3.3.3.3 Multiple generators with priority The generators of higher priority are running first. A given generator in the priority list is running only if the generators of higher priority are running at full load ( gnr,i = 1). If all boilers have the same power output Pn , the number of running generators N gnr,on is given by: | | . | \ | = Pn out gen, H, on gnr, int N (11) Otherwise running boilers have to be determined so that 0 < gnr,j < 1 (see equation (10)) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 27 The load factor gnr,j for the intermittent running generator is calculated by: j Pn, N 1 i i Pn, out gen, H, j gnr, on gnr, _ = − = β (12) where Pn,i nominal power output of generator i running at full load; Pn,j nominal power output of intermittent running generator. 5.3.4 Generators with double service (space heating and domestic hot water production) During the heating season, the heat generator can produce energy for the space heating installation and the domestic hot water (double service). Calculation of the thermal losses for a generator running for domestic hot water service only, is specified in the domestic hot water part of this standard, EN 15316-3-3 [3]. The domestic hot water generation also influences the heating part of a double service generator in respect of:  running temperature of the generator;  running time;  load. The running temperature of the generator may be modified if domestic hot water production is required. The dynamic effects of this temperature modification (heating up, cooling down) are neglected in this part of the standard. The needs for domestic hot water production may extend the heating up period, if the generator is already running at nominal power. The impacts on the time periods (heating up, normal mode, etc.) defined in EN ISO 13790 are neglected. The domestic hot water production increases the load of the double service generator. This effect is taken into account by increasing the generation sub-system load during the considered period by: in dis, W, in dis, H, ctrl out gen, HW, Q Q f Q + ⋅ = (13) and using Q HW,gen,out instead of Q H,gen,out in equation (8). NOTE Equation (13) is the same as equation (2). In general, the considered calculation period is the same for domestic hot water production and for space heating. However, if the domestic hot water is produced only during specific operation modes (e.g. only during normal mode or if a priority control is fitted), the calculation may be performed independently for the two operation modes:  once taking into account t gnr,H (operation time for space heating) and Px,H (calculated with Q H,dis,in and t gnr,H ) and operating conditions for space heating service; UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 28  once taking into account t gnr,W (operation time for domestic hot water production) and Px,W (calculated with Q W,dis,in and t gnr,W ) and operating conditions for domestic hot water production. Losses, auxiliary energy and fuel input for the two operation modes are summed up at the end of the calculation. 5.3.5 Generator thermal losses 5.3.5.1 Generator thermal loss calculation at full load The efficiency at full load gnr,Pn is measured at a reference generator average water temperature θ gnr,w,test,Pn . This efficiency has to be adjusted to the actual generator average water temperature of the individual installation. The temperature corrected efficiency at full load gnr,Pn,corr is calculated by: ) ( m w, gnr, Pn test, w, gnr, Pn corr, Pn gnr, corr Pn, gnr, f − ⋅ + = (14) where gnr,Pn generator efficiency at full load. If the performance of the generator has been tested according to relevant EN standards (see 5.3.2.1), it can be taken into account. If no values are available, default values shall be found in the relevant national annex or in B.3.1; f corr,Pn correction factor taking into account variation of the full load efficiency as a function of the generator average water temperature. The value should be given in a national annex. In the absence of national values, default values are given in B.3.3. If the performance of the generator has been tested according to relevant EN standards (see 5.3.2.1), it can be taken into account; grn,w,test,Pn generator average water temperature at test conditions for full load (see B.3.3); gnr,w,m generator average water temperature as a function of the specific operating conditions (see 5.3.9). In order to simplify the calculations, the efficiencies and heat losses determined at test conditions are adjusted to the actual generator average water temperature. It is allowed, as it is physically correct, to adjust the performance at each load according to the actual generator average water temperature of each load. The corrected generator thermal loss at full load gnr,ls,Pn,corr is calculated by: Pn corr Pn, gnr, corr Pn, gnr, corr Pn, ls, gnr, ) (100 ⋅ − = (15) where Pn generator output at full load. 5.3.5.2 Generator thermal loss calculation at intermediate load The efficiency at intermediate load gnr,Pint is measured at a reference generator average water temperature θ gnr,w,test,Pint . This efficiency has to be adjusted to the actual generator average water temperature of the individual installation. The temperature corrected efficiency at intermediate load gnr,Pint,corr is calculated by: UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 29 ) ( m w, gnr, Pint test, w, gnr, Pint corr, Pint gnr, corr Pint, gnr, f − ⋅ + = (16) where gnr,Pint generator efficiency at intermediate load. If the performance of the generator has been tested according to relevant EN standards (see 5.3.2.1), it can be taken into account. If no values are available, default values shall be found in the relevant national annex or in B.3.1; f corr,Pint correction factor taking into account variation of the efficiency as a function of the generator average water temperature. The value should be given in a national annex. In the absence of national values, default values are given in B.3.3. If the performance of the generator has been tested according to relevant EN standards (see 5.3.2.1), it can be taken into account; gnr,w,test,Pint generator average water temperature (or return temperature to the boiler for condensing boilers) at test conditions for intermediate load (see B.3.3); gnr,w,m generator average water temperature (or return temperature to the generator for condensing boilers) as a function of the specific operating conditions (see 5.3.9). The intermediate load depends on the generator type. Default values are given in D.2. The corrected generator thermal loss at intermediate load Φ gnr,ls,Pint,corr is calculated by: Pint corr Pint, gnr, corr Pint, gnr, corr Pint, ls, gnr, ) (100 ⋅ − = (17) where Pint generator output at intermediate load. 5.3.5.3 Generator thermal loss calculation at 0 % load The generator stand-by heat loss at 0 % load gnr,ls,P0 is determined for a test temperature difference according to relevant testing standards (i.e. EN 297, EN 483/A2, EN 303, EN 13836 and EN 15043). If the performance of the generator has been tested according to relevant EN standards (see 5.3.2.1), it can be taken into account. If no manufacturer or national annex data are available, default values are given in B.3.2. The temperature corrected generator thermal loss at 0 % load Φ gnr,ls,P0,corr is calculated by: 25 , 1 P0 test, gnr, brm i, m w, gnr, P0 ls, gnr, corr P0, ls, gnr, | | . | \ | − ⋅ = (18) where gnr,ls,PO stand-by heat loss at 0 % load at test temperature difference ∆ gnr,test,P0; gnr,w,m generator average water temperature (or return temperature to the generator for condensing boilers) as a function of the specific operating conditions (see 5.3.9); i,brm indoor temperature of the boiler room. Default values are given in B.5.3; ∆ gnr,test,P0 difference between generator average water temperature and test room temperature at test conditions. Default values are given in B.3.2. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 30 5.3.5.4 Boiler thermal loss at specific load ratio gnr and power output Px The specific load ratio gnr of each boiler is calculated according to 5.3.3 and 5.3.4. The actual power output Px of the boiler is given by gnr Pn Px β ⋅ Φ = Φ (19) If Px is between 0 ( gnr = 0) and Pint (intermediate load, gnr = int = Pint / Pn ), the generator thermal loss gnr,ls,Px is calculated by: corr P0, ls, gnr, corr P0, ls, gnr, corr Pint, ls, gnr, Pint Px Px ls, gnr, ) ( + − ⋅ = (20) If Px is between Pint and Pn (full load, gnr = 1), the generator thermal loss Φ gnr,ls,Px is calculated by: corr Pint, ls, gnr, corr Pint, ls, gnr, corr Pn, ls, gnr, Pint Pn Pint Px Px ls, gnr, ) ( + − ⋅ − − = (21) Φ gnr,ls,Px may also be calculated by 2 nd order polynomial interpolation. A formula for such interpolation is given in B.2. The total boiler thermal loss Q gnr,ls during the considered operation time t gnr of the boiler is calculated by: gnr Px ls, gnr, ls gnr, t Q ⋅ = (22) 5.3.5.5 Total generation thermal losses Total generation sub-system thermal losses are the sum of boiler thermal losses: _ = ls gnr, ls gen, H, Q Q (23) 5.3.6 Total auxiliary energy The total auxiliary energy for a boiler is given by: ( ) gnr ci off aux, gnr Px aux, aux gnr, t t P t P W − ⋅ + ⋅ = (24) where P aux,off auxiliary power when the generation system is inactive. If the generator is electrically isolated when inactive, P aux,off = 0. Otherwise P aux,off = P aux,P0 ; t ci is the calculation interval; t gnr is the operation time of the generator within the calculation interval t ci . The average auxiliary power for each boiler P aux,Px is calculated by linear interpolation, according to the boiler load gnr (calculated according to 5.3.3), between:  P aux,Pn auxiliary power of the boiler at full load ( gnr = 1),  P aux,Pint auxiliary power of the boiler at intermediate load ( gnr = int ), UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 31  P aux,P0 auxiliary power of the boiler at stand-by ( gnr = 0), measured according to EN 15456. If no declared or measured data is available, default values are given in B.4. NOTE The corresponding symbols in EN 15456 are: Paux,Pn = Paux,100, Paux,Pint = Paux,30 and Paux,P0 = Paux,sb. If 0 ≤ gnr ≤ int then P aux,Px is given by: ( ) P0 aux, Pint aux, int gnr P0 aux, Px aux, P P P P − ⋅ + = (25) If int < gnr ≤ 1 then P aux,Px is given by: ( ) Pint aux, Pn aux, int int gnr Pint aux, Px aux, 1 P P P P − ⋅ − − + = (26) The generation sub-system auxiliary energy W H,gen,aux is given by: _ = aux gnr, aux gen, H, W W (27) 5.3.7 Recoverable generation system thermal losses 5.3.7.1 Auxiliary energy For the recoverable auxiliary energy, a distinction is made between:  recoverable auxiliary energy transmitted to the heating medium (e.g. water). It is assumed that the auxiliary energy transmitted to the energy vector is totally recovered;  recoverable auxiliary energy transmitted to the heated space. The recovered auxiliary energy transmitted to the heating medium Q gnr,aux,rvd is calculated by: aux rvd, aux gnr, rvd aux, gnr, f W Q ⋅ = (28) where f rvd,aux part of the auxiliary energy transmitted to the distribution sub-system. The value should be given in a national annex. In the absence of national values, a default value is given in B.5.1. If the performance of the generator has been declared by the manufacturer, it can be taken into account. Recovered auxiliary energy already taken into account in efficiency data shall not be calculated for recovery again. It has to be calculated for auxiliary energy need only. NOTE Measured efficiency according to relevant standards usually includes the effect of heat recovered from auxiliary energy for oil heating, combustion air fan, primary pump (i.e. heat recovered from auxiliaries is measured with the useful output). The recoverable auxiliary energy transmitted to the heated space Q gnr,aux,rbl is calculated by: aux rbl, brm aux gnr, rbl aux, gnr, ) (1 f b W Q ⋅ − ⋅ = (29) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 32 where f rbl,aux part of the auxiliary energy not transmitted to the distribution sub-system. The value should be given in a national annex. In the absence of national values, a default value is given in B.5.1. If the performance of the generator has been certified, it can be taken into account; b brm temperature reduction factor depending on location of the generator. The value of b brm should be given in a national annex. In the absence of national values, a default value is given in B.5.3. 5.3.7.2 Generator thermal loss (generator envelope) Only the thermal losses through the generator envelope are considered as recoverable and depend on the burner type. For oil and gas fired boilers, the thermal losses through the generator envelope are expressed as a fraction of the total stand-by heat losses. The recoverable thermal losses through the generator envelope Q gnr,ls,env,rbl are calculated by: gnr env gnr, brm corr P0, ls, gnr, rbl env, ls, gnr, ) (1 t f b Q ⋅ ⋅ − ⋅ = (30) where f gnr,env thermal losses through the generator envelope expressed as a fraction of the total stand-by heat losses. The value of f gnr,env should be given in a national annex. In the absence of national values, default values are given in B.5.2. If the performance of the generator has been tested, it can be taken into account; b brm temperature reduction factor depending on location of the generator. The value of b brm should be given in a national annex. In the absence of national values, a default value is given in B.5.3; t gnr boiler operation time. 5.3.7.3 Total recoverable generation system thermal losses The total recovered auxiliary energy Q H,gen,aux,rvd is calculated by: _ = rvd aux, gnr, rvd aux, gen, H, Q Q (31) The total recoverable generation system thermal losses Q H,gen,ls,rbl are calculated by: _ _ + = rbl aux, gnr, rbl env, ls, gnr, rbl ls, gen, H, Q Q Q (32) 5.3.8 Fuel input Fuel heat input E H,gen,in is calculated according to equation (1). 5.3.9 Operating temperature of the generator The operating temperature of the generator depends on:  type of control;  technical limit of the generator (taken into account by the temperature limitation);  temperature of the distribution sub-system connected to the generator. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 33 The effect of control on the boiler is assumed to be a varying average temperature of the heat emitters. Therefore three types of boiler control are taken into account:  constant water temperature;  variable water temperature depending on the inside temperature;  variable water temperature depending on the outside temperature. The operating temperature of the generator is calculated by: ) , max( x w, gnr, min w, gnr, ltd x, w, gnr, = (33) where gnr,,w,min minimum operating boiler temperature for each generator. If the installation is equipped with several generators, the running temperature limitation used for calculation is the highest value of the temperature limitations of the generators running at the same time. The values should be given in a national annex. In the absence of national values, default values are given in B.3.1; gnr,w,x relevant water temperature during the considered period. A method to calculate this temperature is given in informative Annex H and in Clauses 7 and 8 of EN 15316-2-3:2007. If different heat distribution sub-systems are connected to the generator, the highest temperature among the heat distribution sub-systems or the weighted average according to the relevant annex is used for calculation. 5.4 Boiler cycling method 5.4.1 Principle of the method This calculation method is based on the following principles. The operation time is divided in two parts:  burner on operation t ON ;  burner off operation (stand-by) t OFF . The total time of operation of the generator is t gnr = t ON + t OFF . Thermal losses are taken into account separately for these two periods of time. During burner on operation, the following thermal losses are taken into account:  heat of flue gas with burner on: Q ch,on ;  thermal losses through the generator envelope: Q ge . During burner off operation, the following thermal losses are taken into account:  heat of air flow to the chimney Q ch,off ;  thermal losses through the generator envelope Q ge . Auxiliary energy is considered separately for devices before and after the combustion chamber: UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 34  W br is the auxiliary energy required by components and devices that are before the combustion chamber following the energy path (typically burner fan, see Figure 6); NOTE Typically these components and devices are running only when the burner is on, i.e. during tON.  W pmp is the auxiliary energy required by components and devices that are after the combustion chamber following the energy path (typically primary pump, see Figure 6). NOTE Typically these components and devices are running during the entire operation period of the heat generator, i.e. during tgnr = tON + tOFF. k pmp and k br express the fractions of the auxiliary energy for these appliances recovered to the heating medium (typically the efficiency of the primary pumps and the burner fan). Therefore:  Q br = k br · W br is the auxiliary energy recovered from appliances before the heat generator;  Q pmp = k pmp · W pmp is the auxiliary energy recovered from appliances after the heat generator. Auxiliary energy transformed into heat and emitted to the heated space may be considered separately and is added to the recoverable thermal losses. The basic energy balance of the generation sub-system is: ge off ch, on ch, pmp br cmb out gen, H, Q Q Q Q Q Q Q − − − + + = (34) NOTE This is the same as equation (1) where: ge off ch, on ch, ls gen, H, Q Q Q Q + + = (35) cmb in gen, H, Q E = (36) pmp br rvd aux, gen, H, Q Q Q + = (37) A schematic diagram of the energy balance of the generation sub-system is shown in Figure 6. Figure 6: Energy balance diagram of generation sub-system for boiler cycling method UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 35 Heat losses at test conditions are expressed as a percentage ( ch,on , ch,off and ge ) of a reference power at test conditions. The heat generator is characterised by the following values:  Φ cmb combustion power of the generator, which is the reference power for ch,on (either design or actual value);  Φ ref reference power for the heat loss factors ch,off and ge (usually Φ ref = Φ cmb );  ch,on , ch,off , ge heat loss factors at test conditions;  P br electrical power consumption of auxiliary appliances (before the generator);  k br recovery factor of P br ;  P pmp electrical power consumption of auxiliary appliances (after the generator);  k pmp recovery factor of P pmp ;  θ gnr,w,m,test average boiler water temperature at test conditions for ch,on ;  θ i,brm,test temperature of test room for ge and ch,off ;  ∆θ ge,test = θ gnr,w,m,test - θ i,brm,test at test conditions for ge and ch,off ;  n ch,on , n ch,off , n ge exponents for the correction of heat loss factors. For multistage or modulating boilers, the following additional data is required:  Φ cmb,min minimum combustion power of the generator;  ch,on,min heat loss factor ch,on at minimum combustion power Φ cmb,min ;  P br,min electrical power consumption of auxiliary appliances (before the generator) at minimum combustion power Φ cmb,min . For condensing boilers, the following additional data is required:  wfg temperature difference between boiler return water temperature and flue gas temperature;  X O2,fg,dry dry flue gas oxygen contents. For condensing multistage or modulating boilers, the following additional data is required:  wfg,min temperature difference between boiler return water temperature and flue gas temperature at minimum combustion power;  X O2,fg,dry,min dry flue gas oxygen contents at minimum combustion power. Actual operation conditions are characterised by the following values:  Q H,gen,out heat output to the heat distribution sub-system(s);  θ gnr,w,m average water temperature in the boiler;  θ gnr,w,r return water temperature to the boiler (for condensing boilers); UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 36  θ i,brm boiler room temperature;  k ge,rvd reduction factor taking into account recovery of thermal losses through the generator envelope depending on location of the generator;  cmb load factor. NOTE 1 All powers and the load factor cmb are referred to generator input (combustion power). NOTE 2 Φref is kept formally separate from Φcmb to improve formulas clarity and to enable the use of measured data, if and when available. Data should be declared by the manufacturer or measured, where applicable. If no declared or measured data is available, data shall be found in a relevant national annex. If no national annex is available, default values can be found in Annex D. 5.4.2 Load factor The load factor cmb is the ratio between the time with the burner on and the total time of generator operation (running and stand-by): OFF ON ON gnr ON cmb t t t t t + = = (38) and also ( ) gnr cmb OFF ON cmb ON t t t t ⋅ = + ⋅ = (39) where t gnr total time of generator operation; t ON time with the burner on (fuel valve open, pre- and post-ventilation are not considered); t OFF time with the burner off. The load factor cmb shall either be calculated according to the actual energy Q H,gen,out to be supplied by the generation sub-system or be measured (e.g. by time counters) on existing systems. 5.4.3 Specific thermal losses 5.4.3.1 General Specific heat losses of the generator are given at standard test conditions. Test values shall be adjusted according to actual operation conditions. This applies both to standard test values and to field measurements. 5.4.3.2 Thermal losses through the chimney with the burner on ch,on The correction method for this loss factor takes into account the effects of:  average water temperature in the boiler;  load factor; UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 37  burner settings (power and excess air changing the heat exchange efficiency). Actual specific thermal losses through the chimney with the burner on ch,on,corr are given by: ( ) [ ] on ch, n cmb on ch, corr, test m, w, gnr, m w, gnr, on ch, corr on, ch, f ⋅ ⋅ − + = (40) where ch,on heat losses through the chimney at test conditions (complement to 100 of the combustion efficiency). ch,on is measured with the average water temperature θ gnr,w,m,test . Heat losses through the chimney shall be expressed as a percentage of the combustion power Φ cmb . For the design of new systems, ch,on is the value declared by the manufacturer. For existing systems, ch,on is given by a measure of combustion efficiency. Combustion efficiency measurement shall be realised according to national standards or recommenda- tions. When combustion efficiency is measured, the corresponding average water tempe- rature θ gnr,w,m,test and combustion power cmb shall be measured as well. If no data is available, default values are given in C.2.1, Table C.1. The source of data shall be clearly stated in the calculation report; θ gnr,w,m,test average water temperature in the boiler at test conditions (average of flow and return temperature, usually flow temperature 80 °C, return temperature 60 °C). For the design of new systems, θ gnr,w,m,test is the value declared by the manufacturer. For existing systems, θ gnr,w,m,test is measured together with combustion efficiency. If no data is available, default values are given in C.2.1, Table C.1. The source of data shall be clearly stated in the calculation report. For condensing boilers, return water temperature at test conditions θ gnr,w,r,test shall be used in (40) instead of average water temperature θ gnr,w,m,test; θ gnr,w,m average water temperature in the boiler at actual conditions (average of flow and return temperature). For condensing boilers, return water temperature θ gnr,w,r shall be used in (40) instead of average water temperature θ gnr,w,m; f corr,ch,on correction factor for ch,on . Default values for this factor are given in C.2.1, Table C.1; n ch,on exponent for the load factor cmb . Default values for this exponent are given in C.2.1, Table C.2. cmb raised to n ch,on takes into account the reduction of losses with high intermittencies, due to a lower average temperature of the flue gas (higher efficiency at start). An increasing value of n ch,on corresponds to a higher value of c mass , ch,on , defined as the specific mass of the heat exchange surface between flue gas and water per kW nominal power. NOTE 1 Equation (40) takes into account variation in combustion efficiency depending on average temperature of water in the generator by a linear approximation. The assumption is that temperature difference between water and flue gas is approximately constant (i.e. a 20 °C increase of average water temperature causes a 20 °C increase of flue gas temperature). A 22 °C increase of flue gas temperature corresponds to 1 % increase of losses through the chimney with burner on, hence the default value 0,045 for fcorr,ch,on. Equation (40) does not include the effect of any latent heat recovery. This is done separately (see 5.4.8). NOTE 2 Equation (40) does not take into account explicitly the effect of varying air/fuel ratio. The default constant 0,045 is valid for standard excess air (XO2 = 3 % in dry flue gas). For new systems, a correct setting is assumed. For existing systems, the air/fuel ratio contributes to ch,on. If required, the constant 0,045 may be recalculated according to the actual air/fuel ratio. NOTE 3 Equation (40) does not take into account explicitly the effect of varying combustion power cmb. If the combustion power is significantly reduced, the procedure for existing systems shall be followed (i.e. ch,on shall be measured). UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 38 5.4.3.3 Thermal losses through the generator envelope ge Actual specific thermal losses through the generator envelope ge,corr are given by: ( ) ( ) ge n cmb test brm, i, test m, w, gnr, brm i, m w, gnr, rvd ge, ge corr ge, k ⋅ − − ⋅ ⋅ = (41) where ge heat losses through the generator envelope at test conditions. ge is expressed as a fraction of the reference power Φ ref (usually nominal combustion power of the generator). For the design of new systems, ge is the value declared by the manufacturer. If no data is available, default values are given in C.2.2. The source of data shall be clearly stated in the calculation report; k ge,rvd reduction factor taking into account the location of the generator. k ge,rvd takes into account recovery of thermal losses as a reduction of total losses. Default values are given in C.2.2, Table C.4; θ brm,test temperature of the test room. Default values are given in C.2.2, Table C.4; θ i,brm actual temperature of the room where the generator is installed. Default values are given in C.2.2, Table C.4; n ge exponent for the load factor cmb . Default values for this exponent are given in C.2.2, Table C.5 depending on the parameter c ge , defined as the ratio between the total weight of the boiler (metal + refractory materials + insulating materials) and the nominal combustion power cmb of the boiler. NOTE 1 The factor cmb raised to nge takes into account the reduction of heat losses through the generator envelope if the generator is allowed to cool down during stand-by. This reduction applies only to the specific control option, where the room thermostat stops directly the burner and the circulation pump (in series with the boiler thermostat, solution adopted on small systems only). In all other cases nge = 0 inhibits this correction. NOTE 2 It is assumed that heat losses through the envelope are related to the temperature difference between the average water temperature in the boiler and the temperature of the boiler surroundings. The relation is assumed to be linear (heat conduction through the boiler insulation). NOTE 3 ge can be determined as the difference between the combustion efficiency and the net efficiency of the generator at test conditions (continuous operation). Recovery of thermal losses through the generator envelope is taken into account as a reduction of total losses (by the reduction factor k ge,rvd ). As an alternative, it is possible to determine the actual total generator envelope thermal losses ge,corr from the total heat losses at test conditions ge by: ( ) ( ) ge n cmb test brm, i, test m, w, gnr, brm i, m w, gnr, ge corr ge, ⋅ − − ⋅ = (42) and determine the actual recoverable thermal losses factor, ge,rbl by: ( ) rvd ge, corr ge, rbl ge, 1 k − ⋅ = (43) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 39 5.4.3.4 Thermal losses through the chimney with the burner off ch,off This thermal loss takes into account the stack effect of the chimney, which causes a flow of cold air through the boiler when the burner is off. A correction according to the average water temperature in the boiler and the boiler room temperature is required. A second correction is required when the room thermostat shuts down the circulation pump at the same time as the burner. With this control option, the actual average temperature of the water in the boiler decreases with the load factor. During each burner off period, the maximum energy which can be lost is the heat stored in the boiler (in the metallic parts and in the water). Therefore, the load factor is a function of the heat capacity of the boiler. Actual specific thermal losses through the chimney when the burner is off ch,off,corr are given by: ( ) ( ) of ch, n cmb test brm, i, test m, w, gnr, brm i, m w, gnr, off ch, corr off, ch, ⋅ − − ⋅ = (44) where ch,off heat losses through the chimney when the burner is off at test conditions. ch,off is expressed as a percentage of the reference power Φ ref (usually nominal combustion power of the generator). For the design of new systems, ch,off is the value declared by the manufacturer. For existing systems, ch,off can be calculated by measuring the flow rate and the temperature at the boiler flue gas outlet. If no data is available, default values are given in C.2.3, Table C.6. The source of data shall be clearly stated in the calculation report; n ch,off exponent for the load factor cmb . Default values for this exponent are given in C.2.3, Table C.7 depending on the parameter c ch,off , defined as the ratio between the total weight of the boiler (metal + refractory materials + insulating materials) and the nominal combustion power Φ cmb of the boiler. NOTE The factor cmb raised to nch,off takes into account the reduction of heat losses through the chimney with the burner off if the generator is allowed to cool down during stand-by. This reduction applies only to the specific control option, where the room thermostat stops directly the burner and the circulation pump (in series with the boiler thermostat, solution adopted on small systems only). In all other cases nch,off = 0 inhibits this correction. 5.4.4 Total thermal losses Thermal losses through the chimney with the burner on Q ch,on are given by: ON cmb corr on, ch, on ch, 100 t Q ⋅ ⋅ = (45) Thermal losses through the chimney with the burner off Q ch,off are given by: OFF ref corr off, ch, off ch, 100 t Q ⋅ ⋅ = (46) Thermal losses through the generator envelope Q ge are given by: ( ) ON OFF ref corr ge, ge 100 t t Q + ⋅ ⋅ = (47) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 40 5.4.5 Auxiliary energy For each auxiliary device i of the generator, the following data shall be determined:  Electrical power consumption P i . Values can be:  declared by the manufacturer;  measured;  or default values calculated according to C.3. The source of data shall be clearly stated in the calculation report.  Running time t on,i , as a function of load factor cmb where appropriate (i.e. burner auxiliaries). EXAMPLE 1 Burner fan: ton = cmb · tgnr  Part of the electrical energy converted to heat and recovered to the system before the combustion chamber k br,i (auxiliary energy recovery factor). The default value for k br is given in C.3, Table C.9. EXAMPLE 2 Examples of such auxiliaries are combustion air fan, fuel pump, fuel heaters.  Part of the electrical energy converted to heat and recovered to the system after the generator k pmp,i (auxiliary energy recovery factor). The default value for k pmp is given in C3, Table C.9. EXAMPLE 3 Examples of such auxiliaries are primary pumps. Variable electrical power consumption should be approximated by an equivalent constant average electrical power consumption. The total auxiliary energy required by the generation sub-system W H,gen,aux is given by: _ ⋅ = i on,i aux,i gnr, aux gen, H, t P W (48) The auxiliary energy of devices j before the combustion chamber (i.e. combustion air fan, fuel heater, etc.) which is converted to heat and recovered, is given by: _ ⋅ ⋅ = j br j on, j br, br k t P Q (49) If t on,j = t on for all devices j and assuming P br = P br,j : ON br br br t k P Q ⋅ ⋅ = (50) NOTE tON = tgnr · cmb The auxiliary energy of devices k after the combustion chamber (i.e. primary pump) which is converted to heat and recovered to the system is given by: _ ⋅ ⋅ = k pmp k on, k pmp, pmp k t P Q (51) If t on,k = t gnr for all devices k and assuming P pmp = P pmp,k : gnr pmp pmp pmp t k P Q ⋅ ⋅ = (52) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 41 The total auxiliary energy required by the generation sub-system W H,gen,aux is given by: pmp pmp br br aux gen, H, k Q k Q W + = (53) 5.4.6 Calculation procedure for single stage generators a) Determine the total heat output Q H,gen,out of the generation sub-system, which is equal to Q H,dis,in , total heat to be supplied to the distribution sub-system in the calculation period. For multiple interconnected distribution and/or generation sub-systems, refer to 4.6 and 5.4.9 and then proceed with the present procedure using Q H,gen,out,i for each generator. b) Determine the total time t gnr of operation of the generator (t gnr = t ON + t OFF ). c) Set the load factor cmb = 1. The calculation requires iterations with the load factor cmb approaching the final value. If the value of cmb is known (measured on an existing system), perform step d) and e), skip step f) and g) and proceed to step h) (no iteration required). d) Determine the values of ch,on,corr , ch,off,corr and ge,corr according to 5.4.3 for the current load factor cmb . e) Determine the values of Q pmp , Q br and W H,gen,aux according to 5.4.5 for the current load factor cmb . f) Calculate a new load factor cmb by: corr off, ch, corr on, ch, ref cmb ref br br cmb corr ge, corr off, ch, ref gnr pmp out gen, H, cmb 100 100 P k t Q Q + ⋅ − ⋅ + ⋅ + + ⋅ − ⋅ = (54) g) Repeat steps d), e) and f) until cmb converges. Typically one iteration is enough. More iterations may be required if cmb approaches 0. h) Calculate the energy to be supplied by the fuel by: cmb gnr cmb gen,in H, t E ⋅ ⋅ = (55) i) Calculate the total thermal losses by: pmp br out gen, H, in gen, H, ls gen, H, Q Q Q E Q + + − = (56) There are no recoverable thermal losses, since heat recovery has been taken into account as a reduction of thermal losses through the generator envelope: 0 rbl ls, gen, H, = Q (57) 5.4.7 Multistage and modulating generators 5.4.7.1 General A multistage or modulating generator is characterised by 3 possible states: UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 42  burner off;  burner on at minimum power;  burner on at maximum power. It is assumed that only two situations are possible:  the generator is operating intermittently as a single stage generator at minimum power;  the generator is operating at a constant average power between minimum and maximum power. 5.4.7.2 Additional data required The following additional data are required to characterise a multistage or modulating generator:  Φ cmb,min minimum combustion power of the generator;  ch,on,min heat loss factor ch,on at minimum combustion power Φ cmb,min , as a fraction of Φ cmb,min ;  P br,min electrical power consumption of burner auxiliaries at minimum combustion power. If data from the manufacturer or default values from a national annex are not available, default values are calculated according to C.4. It is assumed that nominal values correspond to maximum power output, therefore:  Φ cmb,max = Φ cmb maximum combustion power of the generator;  ch,on,max = ch,on heat loss factor at maximum combustion power Φ cmb,max . 5.4.7.3 Calculation procedure for multistage or modulating generators The procedure begins following the method described in 5.4.6 for single stage generators, using:  Φ cmb,min instead of Φ cmb ;  ch,on,min instead of ch,on ;  θ gnr,w,test,min instead of θ gnr,w,test ;  P br,min instead of P br . If the load factor cmb converges to a value which is not greater than 1, the procedure for single stage generators is followed up to the end. If the load factor cmb converges to a value greater than 1, then t ON = t gnr and the average combustion power Φ cmb,avg is calculated as follows: a) Determine the total heat output Q H,gen,out of the generation sub-system, which is equal to Q H,dis,in , total heat to be supplied to the distribution sub-system in the calculation period. For multiple interconnected distribution and/or generation sub-systems, refer to 4.6 and 5.4.9 and then proceed with the present procedure using Q H,gen,out,i for each generator. b) Calculate ge,corr according to equation (41) and load factor cmb = 1. c) Calculate ch,on,min,corr and ch,on,max,corr according to equation (40) and load factor cmb = 1. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 43 d) Calculate Q br and Q br,min according to equation (50) using P br , P br,min and cmb = 1. e) Set Φ cmb,avg = Φ cmb. f) Calculate ch,on,avg,corr by: ( ) min cmb, max cmb, min cmb, avg cmb, corr min, on, ch, corr max, on, ch, corr min, on, ch, corr avg, on, ch, − − ⋅ − + = (58) g) Calculate Q br,avg by: ( ) min cmb, max cmb, min cmb, avg cmb, min br, max br, min br, avg br, Q Q Q Q − − ⋅ − + = (59) h) Calculate a new Φ cmb,avg by: 100 1 100 corr avg, on, ch, ref corr ge, gnr avg br, pmp out gen, H, avg cmb, t Q Q Q − ⋅ + − − = (60) i) Repeat steps f), g) and h) until Φ cmb,avg converges. Typically one iteration is enough. j) Calculate the energy to be supplied by the fuel by: gnr avg cmb, gen,in H, t E ⋅ = (61) k) Calculate average power of auxiliaries before the combustion chamber br,avg by: ( ) min cmb, max cmb, min cmb, avg cmb, min br, max br, min br, avg br, − − ⋅ − + = (62) l) Calculate auxiliary energy by: ( ) pmp avg br, gnr aux gen, H, t W + ⋅ = (63) m) Calculate recovered auxiliary energy by: ( ) pmp pmp br avg br, gnr rvd aux, gen, H, k k t W ⋅ + ⋅ ⋅ = (64) n) Calculate total thermal losses by: rvd aux, gen, H, out gen, H, in gen, H, ls gen, H, W Q E Q + − = (65) There are no recoverable thermal losses, since recovery has been taken into account as a reduction of thermal losses through the generator envelope: 0 rbl ls, gen, H, = Q (66) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 44 5.4.8 Condensing boilers 5.4.8.1 Principle of the method The effect of recovery of latent heat of condensation is taken into account as a reduction of ch,on (losses through the chimney with burner on). Recovery of latent heat of condensation is calculated taking into account flue gas temperature and excess air. The connection between return water temperature and flue gas temperature is given by the wfg between flue gas and return water, which characterises the boiler. For multistage boilers, wfg and excess air are specified separately for minimum and maximum combustion power. For modulating boilers, it is assumed that wfg and oxygen contents X O2,fg,dry (excess air) vary linearly between maximum and minimum combustion power. 5.4.8.2 Boiler data To characterise a single stage (on-off) condensing boiler, the following additional data is required:  wfg temperature difference between boiler return water temperature and flue gas temperature. Value should be given by the appliance manufacturer. If this data is not available, it can be either measured on existing system or taken from tables in a national annex. If such information is missing, default values are given in C.5, Table C.14;  X O2,fg,dry flue gas oxygen contents. Value shall be given by the appliance manufacturer. If this data is not available, it can be either measured on existing systems or taken from tables in a national annex. If such information is missing, default values are given in C.5, Table C.14. For multistage or modulating burners, the following additional data is required:  wfg,min temperature difference between boiler return water temperature and flue gas temperature at minimum combustion power. wfg,min shall be given by the appliance manufacturer. If this data is not available, it can be either measured on existing system or taken from tables in a national annex. If such information is missing, default values are given in C.5, Table C.14;  X O2,fg,dry,min flue gas oxygen contents at minimum combustion power cmb,min . Value shall be given by the appliance manufacturer. If this data is not available, it can be either measured on existing system or taken from tables in a national annex. If such information is missing, default values are given in C.5, Table C.14;  wfg,max temperature difference between boiler return water temperature and flue gas temperature at maximum combustion power instead of wfg . wfg,max shall be given by the appliance manufacturer. If this data is not available, it can be either measured on existing system or taken from tables in a national annex. If such information is missing, default values are given in C.5, Table C.14;  X O2,fg,dry,max flue gas oxygen contents at maximum combustion power instead of X O2,fg,dry . Value shall be given by the appliance manufacturer. If this data is not available, it can be either measured on existing system or taken from tables in a national annex. If such information is missing, default values are given in C.5, Table C.14. NOTE wfg,max and XO2,fg,dry,max are the same values as wfg and XO2,fg,dry for single stage boilers. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 45 5.4.8.3 Data on fuel The following data on fuel is required for calculation of recovery of latent heat of condensation:  H s Gross calorific value of the fuel unit;  H i Net calorific value of the fuel unit;  V air,st,dry Stoichiometric dry air as standard volume per unit of fuel ([Nm³/kg] or [Nm³/Nm³]);  V fg,st,dry Stoichiometric dry flue gas as standard volume per unit of fuel ([Nm³/kg] or [Nm³/Nm³]);  m H2O,st Stoichiometric water production per unit of fuel ([kg/kg] or [kg/Nm³]). Data should be given in a national annex. If no national annex is available, default data is given in C.5, Table C.13. 5.4.8.4 Single stage (on-off) boilers Condensing, single stage, boiler fuel energy, auxiliary energy and thermal losses shall be calculated with the same procedure as in 5.4.6 where ch,on,corr is replaced by ch,on,cond given by: ch,on,cond = ch,on,corr – cond (67) where  cond recovered latent heat of condensation at nominal power, as a percentage of Φ cmb , calculated according to 5.4.8.7. 5.4.8.5 Multi stage (stepping) boilers The procedure set out in 5.4.7 shall be followed, where ch,on,max,corr and ch,on,min,corr are replaced by ch,on,max,cond and ch,on,min,cond given by: ch,on,max,cond = ch,on,max,corr – cond,max (68) ch,on,min,cond = ch,on,min,corr – cond,min (69) where  cond,min recovered latent heat of condensation at minimum combustion power, as a percentage of Φ cmb,min ;  cond,max recovered latent heat of condensation at maximum combustion power, as a percentage of Φ cmb,max . cond,min is calculated according to 5.4.8.7 using:  X O2,fg,dry,min instead of X O2,fg,dry ;  wfg,min instead of wfg . cond,max is calculated according to 5.4.8.7 using:  X O2,fg,dry,max instead of X O2,fg,dry ;  wfg,max instead of wfg . UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 46 5.4.8.6 Modulating boilers The procedure set out in 5.4.7 shall be followed, where ch,on,min,corr is replaced by ch,on,min,cond given by: ch,on,min,cond = ch,on,min,corr – cond,min (70) and ch,on,avg is replaced by ch,on,avg,cond given by: ch,on,avg,cond = ch,on,avg,corr – cond,avg (71) where  cond,min recovered latent heat of condensation at minimum combustion power, as a percentage of Φ cmb,min ;  cond,avg recovered latent heat of condensation at average combustion power, as a percentage of Φ cmb,avg . cond,min is calculated according to 5.4.8.7 using:  X O2,fg,dry,min instead of X O2,fg,dry ;  wfg,min instead of wfg . cond,avg is calculated according to 5.4.8.7 using:  X O2,fg,dry,avg instead of X O2,fg,dry ;  wfg,avg instead of wfg . wfg,avg is calculated (linear interpolation of wfg according to combustion power) by: ( ) min cmb, max cmb, min cmb, avg cmb, min wfg, max wfg, min wfg, avg wfg, − − ⋅ − + = (72) X O2,fg,dry,avg is calculated (linear interpolation of X O2,fg,dry according to combustion power) by: ( ) min cmb, max cmb, min cmb, avg cmb, min dry, fg, O2, max dry, fg, O2, min dry, fg, O2, avg dry, fg, O2, X X X X − − ⋅ − + = (73) 5.4.8.7 Calculation procedure of cond NOTE ch,on,cond may be negative when values are based on fuel net calorific value. Total losses will always be positive when referred to gross calorific values according to 4.7. Flue gas temperature (at boiler outlet connection to flue gas) is calculated by: wfg r w, gnr, fg + = (74) where θ gnr,w,r boiler return water temperature, calculated according to Annex H. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 47 Combustion air temperature θ air is assumed either equal to installation room temperature for type B appliances or to external air temperature for type C appliances. Actual amount of dry flue gas V fg,dry is calculated by: dry fg, O2, dry fg,st, dry fg, 20,94 20,94 X V V − ⋅ = (75) Actual amount of dry combustion air V air,dry is calculated by: V air,dry = V air,st,dry + V fg,dry – V fg,st,dry (76) NOTE Vfg,dry – Vfg,st,dry is excess air. Saturation humidity of air m H2O,air,sat and flue gas m H2O,fg,sat shall be calculated according to θ air (combustion air temperature) and θ fg (flue gas temperature) respectively and expressed as kg of humidity per Nm³ of dry air or dry flue gas. Data can be found in the following Table 3. Linear or polynomial interpolation shall be used for intermediate temperatures. Table 3 – Saturation humidity as a function of temperature Temperature (θair or θfg) °C 0 10 20 30 40 50 60 70 Saturation humidity mH2O,air,sat or mH2O,fg,sat kg/Nm³dry 0,00493 0,00986 0,01912 0,03521 0,06331 0,1112 0,1975 0,3596 NOTE Saturation humidity is expressed as kg of water vapour per Nm³ of dry gas (either air or flue gas). Total humidity of combustion air m H2O,air is calculated by: 100 air dry air, sat air, H2O, air H2O, x V m m ⋅ ⋅ = (77) where  x air combustion air relative humidity. Default value is given in C.5, Table C.14. Total humidity of flue gas m H2O,fg is calculated by: 100 fg dry fg, sat fg, H2O, fg H2O, x V m m ⋅ ⋅ = (78) where  x fg flue gas relative humidity. Default value is given in C.5, Table C.14. The amount of condensing water m H2O,cond is calculated by: m H2O,cond = m H2O,st + m H2O,air - m H2O,fg (79) If m H2O,cond is negative, there is no condensation. Then m H2O,cond = 0 and cond = 0. The specific latent heat of condensation h cond,fg is calculated by: UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 48 h cond,fg = 2 500 600 J/kg – θ fg x 2 435 J/kg·°C (80) or h cond,fg = 694,61 Wh/kg – θ fg x 0,676 4 Wh/kg·°C (81) NOTE Use equation (80) or (81) according to the choice of units for energy and time. The condensation heat Q cond is calculated with: Q cond = m H2O,cond · h cond.fg (82) If the calculation is based on net calorific values, then the recovered latent heat of condensation cond is calculated by: i cond cond 100 H Q ⋅ = α (83) If the calculation is based on gross calorific values, then the recovered latent heat of condensation cond is calculated by: s cond cond 100 H Q ⋅ = α (84) NOTE Default values in Annex C are based on net calorific values. 5.4.9 Systems with multiple generators 5.4.9.1 General In general, sub-systems with multiple generators can be calculated as separated generation sub-systems in parallel. Criteria similar to those given in 5.3.3 can be used to split Q H,gen,out amongst available generators. 5.4.9.2 Modular systems A modular system consists of N gnr identical modules or generators, each characterized by a maximum and a minimum combustion power Φ cmb,i,max and Φ cmb,i,min , assembled as a single unit or connected to the same mains. The combustion power of the entire system is calculated by: Φ cmb = Φ cmb,i,max · N gnr (85) 5.4.9.3 Modular systems with hydraulic shutdown of stand-by modules If there is an automatic control system applied, which shuts down and insulates stand-by generators and/or modules from the distribution network, the following procedure shall be followed. The number N gnr,on of running generators and/or modules is calculated as: ( ) 1 int cmb gnr on gnr, + ⋅ = N N (86) where the load factor cmb is calculated for a single stage generator of combustion power Φ cmb . UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 49 The actual performance of the modulating generator is calculated following the procedure for multistage generators and assuming:  Φ cmb,max = Φ cmb,i,max · N gnr,on  Φ cmb,min = Φ cmb,i,min 5.4.9.4 Modular systems without hydraulic shutdown of stand-by modules If there is no control system applied, which shuts down and insulates stand-by generators and/or modules from the distribution network, the following procedure shall be followed. The actual performance of the modulating generator is calculated following the procedure for multistage generators and assuming:  Φ cmb,max = Φ cmb,i,max · N tot ;  Φ cmb,min = Φ cmb,i,min · N tot . UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 50 Annex A (informative) Sample seasonal boiler performance method based on system typology (typology method) A.1 Scope This Annex is an example of a national annex defining a typology method. The example is based on the Seasonal efficiency calculation procedure (SEDB_UK) intended for use in the housing sector of the UK. If there is no such appropriate national annex, this method (system typology) cannot be used. A.2 Limitations in use of this method This procedure is used to determine the seasonal efficiency of gas and oil boilers installed in the UK housing sector. It is named SEDB_UK (Seasonal Efficiency of Domestic Boilers in the UK). This method of calculation is applicable only to boilers for which the full load efficiency and the 30 % part load efficiency values, obtained by the methods deemed to satisfy Council Directive 92/42/EEC about Boiler Efficiency [1], are available. These are net efficiency values (higher efficiency values, referenced to the lower heat value of fuels). It is essential that both test results are available and that the tests are appropriate to the type of boiler as defined in Council Directive 92/42/EEC about Boiler Efficiency [1], otherwise the calculation cannot proceed. If SEDB_UK values are declared, they should be accompanied by the wording given in A.5, which is necessary to avoid confusion with efficiency values calculated by other methods. A.3 Boiler typologies definition For the purpose of this method, the following boiler typologies are defined. regular boiler boiler which does not have the capability to provide domestic hot water directly (i.e. not a combination boiler). It may nevertheless provide domestic hot water indirectly via a separate hot water storage cylinder combination boiler boiler with the ability to provide domestic hot water directly, in some cases containing an internal hot water store instantaneous combination boiler combination boiler without an internal hot water store, or with an internal hot water store of capacity less than 15 litres storage combination boiler combination boiler with an internal hot water store of capacity at least 15 litres but less than 70 litres, or a combination boiler with an internal hot water store of capacity at least 70 litres, in which the feed to the space UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 51 heating circuit is not taken directly from the store. If the store is at least 70 litres and the feed to the space heating circuit is taken directly from the store, refer to definition of combined primary storage unit (CPSU) combined primary storage unit (CPSU) single appliance designed to provide both space heating and domestic hot water, in which there is a burner that heats a thermal store which contains mainly primary water which is in common with the space heating circuit. Capacity of the hot water store is at least 70 litres and the feed to the space heating circuit is taken directly from the store on/off boiler boiler without the capability to vary the fuel burning rate whilst maintaining continuous burner firing. This includes boilers with alternative burning rates set once only at the time of installation, referred to as range rating modulating boiler boiler with the capability to vary the fuel burning rate whilst maintaining continuous burner firing condensing boiler boiler designed to make use of the latent heat released by condensation of water vapour in the combustion flue products. The boiler must allow the condensate to leave the heat exchanger in liquid form by way of a condensate drain. Boilers not so designed, or without the means to remove the condensate in liquid form are called ‘non-condensing’ A.4 Procedure In the procedure, the data are first converted to gross efficiency (lower efficiency values, referenced to the higher heat value of fuels) under test conditions, and then converted to a seasonal efficiency, which applies under typical conditions of use in a dwelling, allowing for standing losses. In this Annex, efficiencies are expressed in percent. Intermediate calculations should be done to at least four decimal places of a percentage, and the final result should be rounded off to one decimal place. The steps are as follows: a) Determine fuel for boiler type. The fuel for boiler type must be one of natural gas, LPG (butane or propane) or oil (kerosene or gas oil). b) Obtain test data. Retrieve the full-load net efficiency Pn,net and 30 % part-load net efficiency Pint,net test results. Tests must have been carried out using the same fuel as the fuel for boiler type. c) Reduce to maximum net efficiency values Pn,net,max and Pint,net,max . Table A.1 gives the maximum values of net efficiency depending on the type of boiler. Reduce any higher net efficiency test values to the appropriate value given in Table A.1. Table A.1 – Maximum net efficiency values Boiler type Efficiency at full load Pn,net,max % Efficiency at 30 % load Pint,net,max % Condensing boilers 101,0 107,0 Non-condensing boilers 92,0 91,0 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 52 d) Convert the full load efficiency and the 30 % part load efficiency from net values to gross values. Use the following equation (A1) with the appropriate factor from Table A.2. net Px, ntg gross Px, f ⋅ = η (A1) Table A.2 – Efficiency conversion factors Fuel Net-to-gross conversion factor f ntg Natural gas 0,901 LPG (propane or butane) 0,921 Oil (kerosene or gas oil) 0,937 e) Categorise the boiler. i) Select the appropriate category for the boiler according to the definitions (see A.3). ii) For a gas or LPG boiler, determine whether or not it has a permanent pilot light:  if it has a permanent pilot light, set f plt = 1;  if not, set f plt = 0. iii) For a storage combination boiler (either on/off or modulating), determine from the test report whether or not the losses from the store are included in the test values reported (this depends on whether or not the store was connected to the boiler during the tests):  if the store loss is included, set f sto = 1;  if not, set f sto = 0. iv) For a condensing combined primary storage unit (CPSU, either on/off or modulating),  set f sto = 1. v) For a storage combination boiler or a CPSU, obtain the store volume, V sto , in litres from the specification of the device and the stand-by loss factor H sby , using the following equations:  if d ins,sto < 10 mm then H sby = 0,0945 – 0,0055 x d ins,sto ;  if d ins,sto ≥ 10 mm then H sby = 0,394 / d ins,sto ; where d ins,sto is the thickness of the insulation of the store in mm. f) Calculate seasonal efficiency. i) Use the boiler category and other characteristics as defined in A.3 (non-condensing or condensing, gas or LPG or oil, on/off or modulating) to look up the appropriate SEDB_UK equation number in Table A.3 and select the appropriate equation from Table A.4 or Table A.5, as applicable. If no equation number is given in Table A.3, the calculation cannot proceed. ii) Substitute the gross full load efficiency Pn,gross and part load efficiency Pint,gross (found in step 4) and f plt , f sto , V sto and H sby (found in step 5) in the equation found in step 6i. Round off the result to one decimal place, i.e. to the nearest 0,1 %. Note the result for the purpose of the declaration in A.5. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 53 iii) Convert the gross seasonal efficiency back to net seasonal efficiency using: gross Px, ntg net Px, 1 f ⋅ = η (A2) Table A.3 – Equation numbers for different boiler types Non-condensing Condensing Gas or LPG Oil L o w - t e m p e r a t u r e Gas or LPG Oil Boiler type O n / o f f M o d u l a t i n g O n / o f f M o d u l a t i n g O n / o f f M o d u l a t i n g O n / o f f M o d u l a t i n g Regular boiler 101 102 201 X X 101 102 201 X Istantaneous combi boiler 103 104 202 X X 103 104 202 X Storage combi boiler 105 106 203 X X 105 106 203 X Combined primary storage unit 107 107 X X X 105 106 X X UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 54 Table A.4 – Seasonal efficiency calculation equations gen for natural gas boilers and LPG boilers Gas or LPG boiler type Eq. no. Equation On/off regular 101 plt gross Pint, gross Pn, gross gen, 4 2,5 2 f ⋅ − − | | . | \ | + = η Modulating regular 102 plt gross Pint, gross Pn, gross gen, 4 2,0 2 f ⋅ − − | | . | \ | + = η On/off instantaneous combination 103 plt gross Pint, gross Pn, gross gen, 4 2,8 2 f ⋅ − − | | . | \ | + = η Modulating instantaneous combination 104 plt gross Pint, gross Pn, gross gen, 4 2,1 2 f ⋅ − − | | . | \ | + = η On/off storage combination On/off combined primary storage unit (condensing only) 105 ( ) plt sto sby sto gross Pint, gross Pn, gross gen, 4 0,209 2,8 2 f V H f ⋅ − ⋅ ⋅ ⋅ + − | | . | \ | + = η Modulating storage combination Modulating combined primary storage unit (condensing only) 106 ( ) plt sto sby sto gross Pint, gross Pn, gross gen, 4 0,209 7 , 1 2 f V H f ⋅ − ⋅ ⋅ ⋅ + − | | . | \ | + = η On/off combined primary storage unit (non-condensing only) Modulating combined primary storage unit (non-condensing only) 107 ( ) plt sto sby gross Pint, gross Pn, gross gen, 4 0,539 2 f V H ⋅ − ⋅ ⋅ − | | . | \ | + = η Table A.5 – Seasonal efficiency calculation equations gen for oil boilers Oil boiler type Eq. No. Equation Regular 201 | | . | \ | + = 2 gross Pint, gross Pn, gross gen, η Instantaneous combination 202 8 , 2 2 gross Pint, gross Pn, gross gen, − | | . | \ | + = η Storage combination 203 ( ) sto sby sto gross Pint, gross Pn, gross gen, 0,209 2,8 2 V H f ⋅ ⋅ ⋅ + − | | . | \ | + = η g) Calculate generation thermal loss. The SEDB_UK method is based on a typological approach using correlations on efficiency values. Therefore it is necessary to express the seasonal performance of generation in absolute values in order to fit the general structure of EN 15316. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 55 The total generation thermal loss Q H,gen,ls is calculated by: net gen, net gen, out gen, H, ls gen, H, 1 Q Q − ⋅ = (A3) h) Calculate fuel heat requirement. The fuel heat requirement E H,gen,in is calculated by: net gen, out gen, H, gen,in H, Q E = (A4) i) Calculate auxiliary energy W H,gen,aux . The auxiliary energy is calculated according to 5.3.6. j) Calculate total recoverable thermal loss. No recoverable generation thermal loss is taken into account. A.5 Declaring values of seasonal efficiency a) Manufacturers wishing to declare the seasonal efficiency of their products as SEDB_UK values can do so provided that: i) they use the SEDB_UK calculation procedure given in A.2 above; ii) and the necessary boiler test data are independently certified. b) Where a manufacturer declares the SEDB_UK, it shall be expressed as: “Seasonal Efficiency (SEDB_UK) = [x] % The test data from which it has been calculated have been certified by [insert name and/or identification of Notified Body].” Data for several products may be presented in tabulated form, in which case the second paragraph of the declaration should be incorporated as a note to the table. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 56 Annex B (informative) Additional formulas and default values for parametering the case specific boiler efficiency method B.1 Information on the method B.1.1 Basic assumptions and intended use This method is intended for use with boilers where data declared according to Council Directive 92/42/EEC [1] are known. This methodology assumes that losses power and auxiliary power are linearly dependant on boiler load in two ranges:  from 0 to intermediate power;  from intermediate power to nominal (maximum) load. The intermediate load is assumed to be the same as defined by Council Directive 92/42/EEC on Boiler Efficiency [1], that is 30 % of maximum load. It is also assumed that efficiencies determined according to testing standards can be corrected using linear functions of the actual boiler operating temperature or boiler installation room temperature. B.1.2 Known approximations The intermediate power should be the minimum power with burner on. The intermediate load of 30 % is kept to facilitate use of data declared according to Council Directive 92/42/EEC. Polynomial interpolation may be used to reduce the influence of this approximation. The assumption of the linear dependence of efficiencies according to boiler temperature is not true when condensation (which is inherently a non linear phenomenon) occurs. Variable values of f corr according to boiler typology have been introduced to reduce the influence of this approximation. The influence of installation room temperature on boiler efficiency at 30 % and 100 % load is neglected. Installation room temperature has an influence only on stand-by losses and therefore on performance in the range from 0 to intermediate load. B.2 Polynomial interpolation formulas The following equation may replace linear interpolation equations (20) and (21): + − ⋅ ⋅ − ⋅ − − ⋅ ⋅ + = ) ( ) ( ) ( Pint Pn Pint Pn corr P0, ls, gnr, corr Pint, ls, gnr, Pn corr P0, ls, gnr, corr Pn, ls, gnr, Pint 2 Px corr P0, ls, gnr, Px ls, gnr, ) ( ) ( ) ( Pint Pn Pint Pn corr P0, ls, gnr, corr Pn, ls, gnr, 2 Pint corr P0, ls, gnr, corr Pint, ls, gnr, 2 Pn Px − ⋅ ⋅ − ⋅ − − ⋅ ⋅ + (B1) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 57 B.3 Generator efficiencies and stand-by losses B.3.1 Default values for generator efficiency at full load and intermediate load as a function of the generator power output The generator efficiency at full load and intermediate load as a function of the generator power output is given by: | | . | \ | ⋅ + = W 000 1 log ltd Pn, 2 1 Pn gnr, c c η (B2) The generator efficiency at intermediate load as a function of the generator power output is given by: | | . | \ | ⋅ + = W 000 1 log ltd Pn, 4 3 Pint gnr, c c η (B3) The generator efficiency at intermediate load for oil-condensing boilers as a function of the generator power output is given by: 1,05 W 000 1 log ltd Pn, 4 3 Pint gnr, | | . | \ | ⋅ + = c c η (B4) where  Pn,ltd nominal power output, limited to a maximum value of 400 kW. If the nominal power output of the generator is higher than 400 kW, then the value of 400 kW is adopted in equations (B2), (B3) and (B4);  c 1 , c 2 , c 3 , c 4 coefficients given in Table B.1. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 58 Table B.1 – Parameters for calculation of generator efficiency and temperature limitation Boiler type Build year c 1 % c 2 % c 3 % c 4 % gnr,w,min °C before 1978 77,0 2,0 70,0 3,0 50 °C Change-fuel boilers 1978 to 1987 79,0 2,0 74,0 3,0 50 °C before 1978 78,0 2,0 72,0 3,0 50 °C 1978 to 1994 80,0 2,0 75,0 3,0 50 °C Solid fuel boilers (fossil fuel) after 1994 81,0 2,0 77,0 3,0 50 °C Standard boilers before 1978 79,5 2,0 76,0 3,0 50 °C 1978 to 1994 82,5 2,0 78,0 3,0 50 °C Atmospheric gas boilers after 1994 85,0 2,0 81,5 3,0 50 °C before 1978 80,0 2,0 75,0 3,0 50 °C 1978 to 1986 82,0 2,0 77,5 3,0 50 °C 1987 to 1994 84,0 2,0 80,0 3,0 50 °C Heating boiler with forced draught burner after 1994 85,0 2,0 81,5 3,0 50 °C before 1978 82,5 2,0 78,0 3,0 50 °C Burner replacement (only heating boiler with forced draught burner) 1978 to 1994 84,0 2,0 80,0 3,0 50 °C Low temperature boilers 1978 to 1994 85,5 1,5 86,0 1,5 35 °C Atmospheric gas boilers after 1994 88,5 1,5 89,0 1,5 35 °C before 1987 86,0 0,0 84,0 0,0 35 °C Circulation water heater (11 kW, 18 kW and 24 kW) 1987 to 1992 88,0 0,0 84,0 0,0 35 °C before 1987 84,0 1,5 82,0 1,5 35 °C 1987 to 1994 86,0 1,5 86,0 1,5 35 °C Heating boiler with forced draught burner after 1994 88,5 1,5 89,0 1,5 35 °C before 1987 86,0 1,5 85,0 1,5 35 °C Burner replacement (only heating boiler with forced draught burner) 1987 to 1994 86,0 1,5 86,0 1,5 35 °C Condensing boilers before 1987 89,0 1,0 95,0 1,0 20 °C 1987 to 1994 91,0 1,0 97,5 1,0 20 °C Condensing boilers after 1994 92,0 1,0 98,0 1,0 20 °C Condensing boilers, improved 1) from 1999 94,0 1,0 103 1,0 20 °C 1) If standard values for "condensing boilers improved" are used for the calculation, the product value for the boiler installed must at least exhibit the above given efficiency. NOTE Test temperatures are given in Tables B.3 and B.4. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 59 B.3.2 Stand-by heat losses Default value for the stand-by heat losses gnr,ls.P0 depending on the generator power output is calculated by: 6 Pn 5 Pn P0 ls, gnr, W 000 1 100 c c | | . | \ | ⋅ ⋅ = (B5) where Pn nominal power output, c 5 , c 6 parameters given in Table B.2. Table B.2 – Parameters for calculation of stand-by heat losses Boiler type Build year c5 % c6 - ∆θ ∆θ ∆θ ∆θgnr,test,P0 °C Change-fuel boilers until 1987 12,5 – 0,28 50 before 1978 12,5 – 0,28 50 1978 to 1994 10,5 – 0,28 50 Solid fuel boiler after 1994 8,0 – 0,28 50 Standard boilers before 1978 8,0 – 0,27 50 1978 to 1994 7,0 – 0,3 50 Atmospheric gas boilers after 1994 8,5 – 0,4 50 before 1978 9,0 – 0,28 50 1978 to 1994 7,5 – 0,31 50 Heating boiler with forced draught burner (oil/gas) after 1994 8,5 – 0,4 50 Low temperature boilers until 1994 7,5 – 0,30 50 Atmospheric gas boilers after 1994 6,5 – 0,35 50 Circulation water heaters (combination boilers 11 kW, 18 kW and 24 kW) until 1994 3,0 0,0 50 Combination boilers KSp a) after 1994 3,0 0,0 50 Combination boilers DL b) after 1994 2,4 0,0 50 until 1994 8,0 – 0,33 50 Heating boiler with forced draught burner (oil/gas) after 1994 5,0 – 0,35 50 Condensing boilers until 1994 8,0 – 0,33 50 Condensing boilers (oil/gas) after 1994 4,8 – 0,35 50 Combination boilers KSp (11 kW, 18 kW and 24 kW) a) after 1994 3,0 0,0 50 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 60 Boiler type Build year c5 % c6 - ∆θ ∆θ ∆θ ∆θgnr,test,P0 °C Combination boilers DL (11 kW, 18 kW and 24 kW) b) after 1994 2,4 0,0 50 a) KSp: Boiler with integrated domestic hot water heating working on the instantaneous principle with small storage tank (2 < V < 10 l). b) DL: Boiler with integrated domestic hot water heating working on the instantaneous principle with heat exchanger (V < 2 l). B.3.3 Correction factor taking into account variation of efficiency depending on generator average water temperature B.3.3.1 Default values Table B.3 – Default values for full load correction factor f corr,Pn Generator type Boiler average water temperature at boiler test conditions for full load gnr,w,test,Pn Correction factor fcorr,Pn Standard boiler 70 °C 0,04 %/°C Low temperature boiler 70 °C 0,04 %/°C Gas condensing boiler 70 °C 0,20 %/°C Oil Condensing boiler 70 °C 0,10 %/°C Table B.4 – Intermediate load correction factor f corr,Pint Generator type Generator average water temperature at boiler test conditions for intermediate load gnr,w,test, Pint Correction factor fcorr,Pint Standard boiler 50 °C 0,05 %/°C Low temperature boiler 40 °C 0,05 %/°C Gas condensing boiler 30 °C (*) 0,20 %/°C Oil Condensing boiler 30 °C (*) 0,10 %/°C (*) Return temperature For a condensing boiler, testing is not made with a defined generator average water temperature (average of the supply and return temperature), but with a return temperature of 30 °C. The efficiency corresponding to this return temperature can be applied for the generator average water temperature of 35 °C. B.3.3.2 Calculated values Correction factor f corr,Pn may be calculated using efficiency data from additional tests performed at a lower average water temperature, using the following equation: UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 61 Pn test, w, gnr, add Pn, test, w, gnr, add Pn, Pn Pn corr, f − − = (B6) where Pn full load efficiency at standard test conditions with average water temperature gnr,w,test,Pn; Pn,add full load efficiency with average water temperature gnr,w,test,Pn,add . Correction factor f corr,Pint may be calculated using efficiency data from additional tests performed at a higher average water temperature, using the following equation: Pint test, w, gnr, add Pint, test, w, gnr, add Pint, Pint Pint corr, f − − = (B7) where Pint intermediate load efficiency at standard test conditions with average water temperature gnr,w,test,Pint; Pint,add intermediate load efficiency with average water temperature gnr,w,test,Pint,add . B.4 Auxiliary energy Default value for the power consumption of auxiliary equipment is calculated by: n c c P | | . | \ | ⋅ + = W 000 1 Pn 8 7 Px aux, (B8) where Pn nominal power output; c 7 , c 8 , n parameters given in Table B.5. Table B.5 – Parameters for calculation of power consumption of auxiliary equipment Boiler type Load c7 W c8 W n Pn 0 45 0,48 Pint 0 15 0,48 Change-fuel boilers P0 15 0 0 Pn 40 2 1 Pint 40 1,8 1 Automatically-fed pellet central boiler 1) P0 15 0 0 Pn 60 2,6 1 Pint 70 2,2 1 Automatically-fed wood chips central boiler 1) P0 15 0 0 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 62 Boiler type Load c7 W c8 W n Standard boiler Pn 40 0,148 1 Pint 40 0,148 1 Atmospheric gas boilers P0 15 0 0 Pn 0 45 0,48 Pint 0 15 0,48 Heating boiler with forced draught burner (oil/gas) P0 15 0 0 Low temperature boilers Pn 40 0,148 1 Pint 40 0,148 1 Atmospheric gas boilers P0 15 0 0 Pn 0 45 0,48 Pint 0 15 0,48 Circulation water heaters P0 15 0 0 Pn 0 45 0,48 Pint 0 15 0,48 Heating boiler with forced draught burner (oil/gas) P0 15 0 0 Condensing boilers Pn 0 45 0,48 Pint 0 15 0,48 Condensing boilers (oil/gas) P0 15 0 0 1) With the use of fan-assisted firing, the values for Pn and Pint shall be increased by 40 %. B.5 Recoverable generation thermal losses B.5.1 Auxiliary energy Default value of the part of the auxiliary energy transmitted to the distribution sub-system f rvd,aux is 0,75. The part of the auxiliary energy transmitted to the heated space f rbl,aux is calculated by: aux rvd, aux rbl, 1 f f − = (B9) B.5.2 Generator envelope The part of stand-by heat losses attributed to heat losses through the generator envelope is given by f gnr,env . Default values of f gnr,env are given in Table B.6. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 63 Table B.6 – Part of stand-by heat losses attributed to losses through the generator envelope Burner type fgnr,env Atmospheric burner 0,50 Fan assisted burner 0,75 B.5.3 Default data according to boiler location Table B.7 – Temperature reduction factor and default installation room temperature Generator location Temperature reduction factor bbrm - Installation room temperature θ θθ θi,brm °C Outdoors 1 θext In the boiler room 0,3 13 Under roof 0,2 5 Inside heated space 0,0 20 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 64 Annex C (informative) Default values for parametering the boiler cycling method C.1 Information on the method C.1.1 Basic assumptions and intended use This method is intended:  for use with existing boilers where data declared according to Council Directive 92/42/EEC [1] are not known;  to determine the effect of operating conditions on performances of condensing boilers. This methodology is based on a physical analysis of losses (indirect method) and takes into account two operating conditions:  boiler with burner on;  boiler with burner off (stand-by). Latent heat recovery is calculated separately from sensible heat losses. Data for heating system operating conditions, boiler and fuel are kept separate. This methodology is suitable for on-off, modulating, modular and condensing boilers, as well as for their combinations (like modulating, condensing boilers). All data given in this Annex are based on net calorific values H i . If losses are to be calculated with respect to gross calorific value H s , this is done with the procedure given in 4.7. C.1.2 Known approximations Additional losses during ignition cycles (ventilation before ignition) are not taken into account. Losses through the chimney with burner off are not easily measured. However, this loss factor has a reduced impact in modern boilers with air intake closure at stand-by. C.2 Default specific losses C.2.1 Default data for calculation of thermal losses through the chimney with burner on Table C.1 – Default value of θ θθ θ gnr,w,m,test , ch,on and f corr,ch,on Description θ θθ θ gnr,w,m,test °C ch,on % f corr,ch,on %/°C Atmospheric boiler 70 12 0,045 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 65 Description θ θθ θ gnr,w,m,test °C ch,on % f corr,ch,on %/°C Force draught gas boiler 70 10 0,045 Liquid fuel boiler 70 11 0,045 Condensing boiler 60 1) 6 0,045 1) Return temperature for condensing boilers. Table C.2 – Default value of exponent n ch,on Description c mass,ch,on kg/kW n ch,on - Wall mounted boiler < 1 0,05 Steel boiler 1 to 2 0,1 Cast iron boiler > 2 0,15 NOTE cmass,ch,on is the ratio between the mass of the heat exchange surface between flue gas and water and nominal combustion power in kg/kW. C.2.2 Default values for calculation of thermal losses through the generator envelope The default losses through the boiler envelope ge are given by: | | . | \ | ⋅ − = W 000 1 log cmb 2 1 ge c c α (C1) where c 1 , c 2 parameters given in Table C.3; Φ cmb boiler nominal combustion power. Table C.3 – Default value of parameters c 1 and c 2 Boiler insulation type c 1 % c 2 % Well insulated, high efficiency new boiler 1,72 0,44 Well insulated and maintained 3,45 0,88 Old boiler with average insulation 6,90 1,76 Old boiler, poor insulation 8,36 2,2 No insulation 10,35 2,64 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 66 Table C.4 – Default value of factor k ge,rvd and installation room temperature i,brm Boiler type and location k ge,rvd - θ θθ θ i,brm,test °C θ θθ θ i,brm °C Boiler installed within the heated space 0,1 20 Atmospheric boiler installed within the heated space 0,2 20 Boiler installed within a boiler room 0,7 13 Under roof 0,8 5 Boiler installed outdoors 1,0 20 External temperature Default value for θ gnr,w,m,test is 70 °C. Table C.5 – Default value of exponent n ge Description c ge kg/kW n ge - The primary pump is always running 0,0 The primary pump stops when the burner turns off and both are controlled by the room thermostat:  wall mounted boiler  steel boiler  cast iron boiler < 1 1 to 3 > 3 0,15 0,10 0,05 NOTE cge is the ratio between the total weight of the boiler (metal + refractory materials + insulating materials) and the nominal combustion power Φcmb of the boiler in kg/kW. C.2.3 Default values for calculation of thermal losses through the chimney with the burner off Table C.6 – Default value of ch,off Description ch,off % Liquid fuel or gas fired boiler with the fan before the combustion chamber and automatic closure of air intake with burner off: Premixed burners 0,2 0,2 Wall mounted, gas fired boiler with fan and wall flue gas exhaust 0,4 Liquid fuel or gas fired boiler with the fan before the combustion chamber and no closure of air intake with burner off: Chimney height 10 m Chimney height > 10 m 1,0 1,2 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 67 Description ch,off % Atmospheric gas fired boiler: Chimney height 10 m Chimney height > 10 m 1,2 1,6 Table C.7 – Default value of exponent n ch,off Description c ch,off kg/kW n ch,off - The primary pump is always running 0,0 The primary pump stops when the burner turns off and both are controlled by the room thermostat  wall mounted boiler  steel boiler  cast iron boiler < 1 1 to 3 > 3 0,15 0,10 0,05 NOTE cch,off is the ratio between the total weight of the boiler (metal + refractory materials + insulating materials) and the nominal combustion power Φcmb of the boiler in kg/kW. Default value for θ i,brm,test is 20 °C. Default value for θ gnr,w,m,test is 70 °C. C.3 Default values for calculation of auxiliary energy The default auxiliary power P br and P pmp are given by n c c P | | . | \ | ⋅ + = W 1000 cmb 4 3 x (C2) where Φ cmb is the boiler nominal combustion power. Table C.8 – Default value of c 3 and c 4 for the calculation of electrical power consumption of auxiliary devices Description c 3 W c 4 W n - P br , atmospheric gas boilers 40 0,148 1 P br , forced draught burners 0 45 0,48 P br , automatically-fed pellet central boiler 1) 40 2 1 P br , automatically-fed wood chips central boiler 1) 60 2,6 1 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 68 Description c 3 W c 4 W n - P pmp , primary pump (all boilers) 100 2 1 1) With the use of fan-assisted firing, the values for Pn and Pint shall be increased by 40 %. NOTE If there is no primary pump or if it is taken into account in the distribution part (see Figures 3 and 4) then Ppmp = 0 Table C.9 – Default value of auxiliary energy recovery factors Description Value - k br 0,8 k pmp 0,8 C.4 Additional default data for multistage and modulating burners The default minimum combustion power of the boiler is given by: Φ cmb,min = Φ cmb · f min (C3) where f min parameter given in Table C.10; Φ cmb boiler nominal (maximum) combustion power. Table C.10 – Parameter f min for multistage and modulating burners Description f min - Gas boiler 0,3 Liquid fuel boiler 0,5 Table C.11 – Default value of θ θθ θ gnr,w,m,test,min and ch,on,min Description θ θθ θ gnr,w,m,test,min °C ch,on,min % Atmospheric boiler 70 11 Force draught gas boiler 70 9 Oil boiler 70 10 Condensing boiler 50 1) 5 1) Return temperature for condensing boilers. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 69 The default auxiliary power P br,min is calculated with equation (C2) using c 3 , c 4 and n given in Table C.12. Table C.12 – Default value of c 3 , c 4 and n for the calculation of electrical power consumption of auxiliary devices at minimum combustion power Description c 3 W c 4 W n - P br , atmospheric gas boilers 20 0,148 1 P br , forced draught burners 0 15 0,48 P br , automatically-fed pellet central boiler 1) 60 1,8 1 P br , automatically-fed wood chips central boiler 1) 70 2,2 1 1) With the use of fan-assisted firing, the values for Pn and Pint shall be increased by 40 %. C.5 Additional default data for condensing boilers Table C.13 – Default fuel data for condensation heat recovery calculation Fuel Property Symbol Unit Natural gas (Groningen) Propane Butane Light oil EL Unit mass of fuel 1 Nm³ 1 Nm³ 1 Nm³ 1 kg Gross calorific value Hs kJ/kg or kJ/Nm³ 35 169 kJ/Nm³ 101 804 kJ/Nm³ 131 985 kJ/Nm³ 45 336 kJ/kg Net calorific value Hi kJ/kg or kJ/Nm³ 31 652 kJ/Nm³ 93 557 kJ/Nm³ 121 603 kJ/Nm³ 42 770 kJ/kg Stoichiometric dry air Vair,st,dry Nm³/kg or Nm³/Nm 8,4 Nm³/Nm³ 23,8 Nm³/Nm³ 30,94 Nm³/Nm³ 11,23 Nm³/kg Stoichiometric dry flue gas Vfg,st,dry Nm³/kg or Nm³/Nm 7,7 Nm³/Nm³ 21,8 Nm³/Nm³ 28,44 Nm³/Nm³ 10,49 Nm³/kg Stoichiometric water production mH2O,st kg/kg or kg/Nm³ 1,405 kg/Nm³ 3,3 kg/Nm³ 4,03 kg/Nm³ 1,18 kg/kg UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 70 Table C.14 – Default values for the calculation of cond Description Symbol Unit Case Value Combustion air relative humidity x air % All cases 50 Flue gas relative humidity x fg % All cases 100 gnr,Pn 102 20 Temperature difference between boiler return water temperature and flue gas temperature wfg °C gnr,Pn < 102 60 gnr,Pmin 106 5 Temperature difference between boiler return water temperature and flue gas temperature at minimum power wfg,min °C gnr,Pn < 106 20 Flue gas oxygen contents at maximum combustion power X O2,fg,dry - All cases 6 Modulation of both air and gas 6 Flue gas oxygen contents at minimum combustion power X O2,fg,dry,min - Only gas modulation 15 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 71 Annex D (informative) General part default values and information D.1 Control factor Table D.1 – Default values for control factor f ctrl in equation (2) Description f ctrl All control types 1,0 Other values may be specified in a national annex, provided that emission control losses have not been taken into account in the emission part (EN 15316-2-1). NOTE In the EN 15316-X-X series of standards, the effect of heat emission control is taken into account in the emission and control part (EN 15316-2-1). The effect of the control of generation is taken into account through losses and efficiency corrections according to the operating temperature of the generator. Table D.2 is an example of such table to be given in a national annex. Table D.2 – Sample default national table for control factor in equation (2) Boiler type Control type f ctrl Floor standing boiler Outdoor temperature controlled 1,00 Outdoor temperature controlled 1,03 Wall hanged boiler Room temperature controlled 1,06 D.2 Intermediate load Intermediate load int is given by: Φ int = Φ Pn · int (D1) For gas and oil fuelled generators, the default value of int is 0,3. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 72 Annex E (informative) Calculation example for seasonal boiler performance method based on system typology E.1 Introduction This example is based on the method described in Annex A. E.2 Input data Table E.1 – Boiler data Description Symbol Value Boiler type Condensing boiler Nominal power Pn 70 kW gnr,Pn 96 % (full-load net efficiency) Efficiency test results produced in accordance with standard tests as required for the Council Directive 92/42/EEC about Boiler Efficiency [1] gnr,Pint 106 % (30 % part-load net efficiency) Auxiliary electric power at full load Paux,Pn 210 W Auxiliary electric power at intermediate load Paux,Pint 60 W Auxiliary electric power at zero load Paux,P0 10 W Fuel used Natural gas Ignition method No permanent pilot flame Burner type Modulating, fan assisted Table E.2 – Data according to other parts of this standard Description Symbol Value Heat output QH,gen,out 465,7 GJ = 129,36 MWh NOTE Example estimated as 220 days x 86 400 s/day x 70 000 W x 0,35 = 465,7 GJ. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 73 E.3 Calculation procedure Table E.3 – Calculation procedure Procedure step References Calculation details and results 1 Determine fuel for boiler type Natural gas 2 Obtain test data gnr,Pn = 96 %; gnr,Pint = 106 % 3 Reduce to maximum net efficiency values (Table A.1) Table A.1 Pn,net,max = 101 % hence gnr,Pn,net = 96 % Pint,net,max = 107 % hence gnr,Pint,net = 106 % 4 Convert the efficiencies from net to gross values Table A.2 Eq. (A1) Net-to-gross conversion factor: fntg = 0,901 gnr,Pn,gross = 96 % x 0,901 = 86,5 % gnr,Pint,gross = 106 % x 0,901 = 95,5 % 5 Categorise the boiler (i) Select the boiler category condensing, natural gas fuelled, modulating, regular boiler (ii) If a gas or LPG boiler, permanent pilot light fplt = 0 (no permanent pilot light) (iii) For a storage combination boiler Not a storage combination boiler (iv) For a condensing combined primary storage unit Not a CPSU (v) For a storage combination boiler or a CPSU Not a storage combination boiler or a CPSU 6 Calculate seasonal efficiency (i) Choose appropriate SEDB_UK equation Table A.3 Table A.4 Table A.5 Equation n° 102 selected plt gross Pint, gross Pn, gross gen, 4 2,0 2 f ⋅ − − | | . | \ | + = η (ii) Substitute values 0 4 2,0 2 % 95,5 % 86,5 gross gen, × − − | . | \ | + = η = 89,0 % (iii) Convert back to net seasonal efficiency Eq. (A2) % 89 0,901 1 net gen, ⋅ = η = 98,8 % 7 Calculate total generation thermal loss Eq. (A3) 98,8% 98,8% 100 GJ 465,7 ls gen, H, − ⋅ = Q = 5,75 GJ = 1,6 MWh 8 Calculate fuel heat requirement Eq. (A4) % 98,8 100 GJ 465,7 in gen, H, × = E = 471,4 GJ = 130,96 MWh 9 Calculate auxiliary energy Calculate generation average power 5.3.3.1 Eq. (8) s 000 008 19 GJ 465,7 out gen, H, = = 24,5 kW Calculate load factor 5.3.3.2 Eq. (9) kW 70 kW 24,5 gnr = β = 0,35 Select equation 5.3.6 gnr > int then use equation (26) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 74 Procedure step References Calculation details and results Calculate actual auxiliary power 5.3.6 Eq. (26) ( ) W 60 W 210 0,3 1 0,3 0,35 W 60 Px aux, − × − − + = P = 70,7 W Calculate total auxiliary energy 5.3.6 Eq. (24) s 0 W 0 s 000 008 19 W 70,7 aux gnr, × + × = W = 1,034 GJ = 373 kWh 10 Calculate total recoverable thermal loss QH,gen,ls,rbl = 0 No recoverable generation thermal loss is taken into account E.4 Output data (connection to other parts of EN 15316) Table E.4 – Output data Description Symbol Value Fuel heat requirement EH,gen,in 471,4 GJ = 130 960 kWh Total generation thermal loss QH,gen,ls 5,75 GJ = 1 600 kWh Auxiliary energy WH,gen,aux 1,034 GJ = 373 kWh Recoverable thermal loss QH,gen,ls,rbl 0 J = 0 kWh UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 75 Annex F (informative) Calculation examples for case specific boiler efficiency method F.1 Condensing boiler example, data declared by the manufacturer F.1.1 Input data Table F.1 – Boiler data Description Symbol Value Boiler type Condensing boiler Nominal power (heat output) Pn 70 kW gnr,Pn 96 % (full-load net efficiency) gnr,w,test,Pn = 70 °C Efficiency test results produced in accordance with standard tests as required for the Council Directive 92/42/EEC about Boiler Efficiency [1] gnr,Pint 106 % (30 % part-load net efficiency) gnr,w,test,Pint = 30 °C (return temperature) Auxiliary electric power at full load Paux,Pn 210 W Auxiliary electric power at intermediate load Paux,Pint 60 W Auxiliary electric power at zero load Paux,P0 10 W Fuel used Natural gas Burner type Modulating, fan assisted Boiler location Boiler room Type of control Depending on outside temperature Generation circuit typology Direct connection of boiler Table F.2 – Data according to design or to other parts of this standard Description Symbol Value Operation time of the generator tgen 2 592 000 s = 720 h (*) Generator heat output QH,gen,out 80,9 GJ = 22 472 kWh Generation average temperature (**) θgen,f 48,9 °C Generation return temperature (**) θgen,r 37,7 °C Distribution flow rate V'dis 1 207 l/h (*) Example estimated as 30 days, continuous operation (**) Generation temperatures are equal to distribution temperatures. See calculation example in H.6. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 76 F.1.2 Calculation procedure Table F.3 – Calculation procedure Procedure step References Calculation details and results Calculation of boiler average and return temperature H.2 Direct connection of the generator θgnr,w,m = θgen,m = 48,9 °C θgnr,w,r = θgen,r = 37,7 °C Calculation of generation average power 5.3.3.1 Eq. (8) s 000 592 2 GJ 80,9 out gen, H, = = 31,2 kW Calculation of load factor 5.3.3.2 Eq. (9) kW 70 kW 31,2 gnr = β = 0,446 (single boiler, only heating load) Calculation of corrected boiler efficiency at full load 5.3.5.1 Table B.3 Eq. (14) fcorr,Pn = 0,20 %/°C (Table B.3, gas condensing boiler) gnr,w,test,Pn = 70 °C (Table B.3, gas condensing boiler) C) 48,9 C (70 C %/ 0,20 % 96 corr Pn, gnr, ° − ° × ° + = η = 102,4 % Calculation of corrected thermal losses at full load 5.3.5.1 Eq. (15) kW 70 102,4% 102,4%) (100% corr Pn, ls, gnr, × − = = - 1 674 W Calculation of corrected boiler efficiency at intermediate load 5.3.5.2 Table B.4 Eq. (16) fcorr,Pint = 0,20 %/°C (Table B.4, gas condensing boiler) gnr,test,Pint = 30 °C (Table B.4, gas condensing boiler) C) 37,7 C (30 C %/ 0,20 106% corr Pint, gnr, ° − ° × ° + = η = 104,45 % Calculation of corrected thermal losses at intermediate load 5.3.5.2 Eq. (17) 21kW 104,45% 104,45%) (100% corr Pint, ls, gnr, × − = = - 895 W Calculation of boiler stand-by heat loss at 0 % load B.3.2 Table B.2 Eq. (B5) c5 = 4,8 % (Table B.2, gas condensing boiler, after 1994) c6 = - 0,35 (Table B.2, gas condensing boiler, after 1994) ∆θgnr,test,P0 = 50 °C (Table B.2, gas condensing boiler, after 1994) 0,35 W 000 1 W 000 70 100 4,8 W 000 70 P0 ls, gnr, − | | . | \ | × × = = 760 W Calculation of corrected thermal losses at 0 % load 5.3.5.3 Table B.7 Eq. (18) θi,brm = 13 °C (Table B.7, in the boiler room) 1,25 corr P0, ls, gnr, C 50 C 13 C 48,9 W 760 | | . | \ | ° ° − ° × = = 502 W Calculation of corrected thermal losses at actual load 5.3.5.4 Eq. (21) Equation (21) because Px = H,gen,out > Pint W 895 W) 895 W 674 1 ( kW 21 kW 70 kW 21 kW 31,2 Px ls, gnr, − + − × − − = = - 1 057 W Calculation of total generator thermal loss 5.3.5.4 Eq. (22) Qgnr,ls = - 1,026 kW x 720 h = - 761 kWh = - 2 740 MJ Calculation of total generation thermal loss 5.3.5.5 Eq. (23) _ = ls gnr, ls gen, H, Q Q = - 761 kWh = - 2 740 MJ Calculation of auxiliary power at actual load 5.3.6 Eq. (26) Equation (26) because gnr > int ( ) W 60 W 210 0,30 1 0,30 0,446 W 60 Px aux, − × − − + = P = 91,3 W UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 77 Procedure step References Calculation details and results Calculation of generator total auxiliary energy 5.3.6 Eq. (24) Wgnr,aux = 91,3 W x 720 h + 0 W x (720 h – 720 h) = 65,7 kWh Calculation of generation total auxiliary energy 5.3.6 Eq. (27) _ = aux gnr, aux gen, H, W W = 65,7 kWh = 236,5 MJ Calculation of generator recovered auxiliary energy 5.3.7.1 No recovered auxiliary energy is explicitly taken into account because it is already included in test data Qgnr,aux,rvd = 0 Calculation of generator recoverable auxiliary energy (to the heated space) B.5.1 Eq. (B9) Table B.7 5.3.7.1 Eq. (29) frvd,aux = 0,75 frbl,aux = 1 – 0,75 = 0,25 bbrm = 0,3 (Table B.7, in the boiler room) Qgnr,aux,rbl = 65,7 kWh x (1 – 0,3) x 0,25 = 11,5 kWh = 41,4 MJ Calculation of generator thermal losses (generator envelope) 5.3.7.2 Table B.6 Eq. (30) fgnr,env = 0,75 (Table B.6, fan assisted burner) Qgnr,ls,env,rbl = 502 W x (1 – 0,3) x 0,75 x 720 h = 73,1 kWh = 263,3 MJ Calculation of total generation recovered auxiliary energy 5.3.7.3 Eq. (31) No recovered auxiliary energy is explicitly taken into account because it is already included in test data, hence QH,gen,aux,rvd = 0 Calculation of total generation recoverable thermal losses 5.3.7.3 Eq. (32) QH,gen,ls,rbl = 73,1 kWh + 11,5 kWh = 84,6 kWh = 304,7 MJ Calculation of total generation heat input 5.3.8 Eq. (1) EH,gen,in = 22 472 kWh – 0 kWh – 761 kWh = 21 711 kWh = 78 160 MJ F.1.3 Output data (connection to other parts of EN 15316) Table F.4 – Output data Description Symbol Value Fuel heat requirement EH,gen,in 21 711 kWh = 78 160 MJ Total generation thermal loss QH,gen,ls - 761 kWh = - 2 740 MJ Auxiliary energy WH,gen,aux 65,7 kWh = 236,5 MJ Recoverable thermal loss QH,gen,ls,rbl 84,6 kWh = 304,7 MJ F.1.4 Conversion of net values to gross values If losses are to be calculated according to gross calorific value, then the following procedure applies. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 78 Table F.5 – Net to gross conversion procedure Procedure step References Calculation details and results Calculation of the latent heat of condensation 4.7 Eq. (4) Table C.13 Default values from Table C.13 for natural gas: Hs = 35,17 MJ/Nm³ Hi = 31,65 MJ/Nm³ 3 3 3 lat 31,65MJ/Nm 31,65MJ/Nm MJ/Nm 35,17 MJ 160 78 − × = Q = 8 693 MJ = 2 415 kWh Correction of fuel input 4.7 Eq. (5) EH,gen,in,grs = 78 160 MJ + 8 693 MJ = 86 852 MJ = 24 126 kWh Correction of total losses 4.7 Eq. (6) QH,gen,ls,grs = - 2 740 MJ + 8 693 MJ = 5 952 MJ = 1 653 kWh F.2 Standard boiler example, default data F.2.1 Input data Table F.6 – Boiler data Description Symbol Value Boiler type Standard, atmospheric boiler Nominal power (heat output) Pn 70 kW Build year 1988 Fuel used Natural gas Burner type Single stage, on-off Burner location Boiler room Type of control Constant temperature = 70 °C Generation circuit typology Independent flow rate Table F.7 – Data according to design or to other parts of this standard Description Symbol Value Operation time of the generator tgen 2 592 000 s = 720 h (*) Generator heat output QH,gen,out 80,9 GJ = 22 472 kWh Generation flow temperature θgen,f 70 °C Generation return temperature (**) θgen,r 37,7 °C Distribution flow rate V'dis 1 207 l/h Generation flow rate V'gen 6 000 l/h (*) Example estimated as 30 days, continuous operation. (**) Generation return temperature is equal to return distribution. See calculation example in H.6. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 79 F.2.2 Calculation procedure Table F.8 – Calculation procedure Procedure step References Calculation details and results Calculation of generation average power 5.3.3.1 Eq. (8) s 000 592 2 GJ 80,9 out gen, H, = = 31,2 kW Calculation of boiler flow, return and average temperature H.3 Eq. (H4) Eq. (H5) H.5 Eq. (H11) Independent flow rate. Generation flow rate is higher than distribution flow rate θgnr,w,f = 70 °C (design and set value) θ gnr,w,r = m³/s 10 1,67 C J/kg 186 4 kg/m³ 1000 W 200 31 C 70 3 − × × ° ⋅ × − ° = 65,5 °C θgnr,w,m = 2 C 65,5 C 70 ° + ° = 67,8 °C Calculation of load factor 5.3.3.2 Eq. (9) kW 70 kW 31,2 gnr = β = 0,446 (single boiler, only heating load) Calculation of full load efficiency B.3.1 Table B.1 Eq. (B2) c1 = 82,5 % (Table B.1, atmospheric gas boiler, 1978 to 1994) c2 = 2,0 % (Table B.1, atmospheric gas boiler, 1978 to 1994) gnr,Pn = | | . | \ | × + W 000 1 W 000 70 log 2,0% 82,5% = 86,2 % Calculation of corrected boiler efficiency at full load 5.3.5.1 Table B.3 Eq. (14) fcorr,Pn = 0,04 %/°C (Table B.3, standard boiler) gnr,w,test,Pn = 70 °C (Table B.3, standard boiler) gnr,Pn,corr = 86,2 % + 0,04 %/°C x (70 °C - 67,8 °C) = 86,3 % Calculation of corrected boiler thermal losses at full load 5.3.5.1 Eq. (15) kW 70 % 86,3 %) 86,3 (100% corr Pn, ls, gnr, × − = = 11 132 W Calculation of intermediate load efficiency B.3.1 Table B.1 Eq. (B3) c3 = 78,0 % (Table B.1, atmospheric gas boiler, 1978 to 1994) c4 = 3,0 % (Table B.1, atmospheric gas boiler, 1978 to 1994) gnr,Pint = | | . | \ | × + W 000 1 W 000 70 log 3,0% 78% = 83,5 % Calculation of corrected boiler efficiency at intermediate load 5.3.5.2 Table B.4 Eq. (16) fcorr,Pint = 0,05 %/°C (Table B.4, standard boiler) gnr,w,test,Pint = 50 °C (Table B.4, standard boiler) gnr,Pint,corr = 83,5 % + 0,05 %/°C x (50 °C - 67,8 °C) = 82,6 % Calculation of corrected boiler thermal losses at intermediate load 5.3.5.2 Eq. (17) Pint = 30 % x Pn = 21 kW kW 21 % 82,6 %) 82,6 % (100 corr Pint, ls, gnr, × − = = 4 409 W Calculation of boiler stand-by heat loss at 0 % load B.3.2 Table B.2 Eq. (B5) c5 = 7,0 % (Table B.2, atmospheric gas boiler, 1978 to 1994) c6 = - 0,30 (Table B.2, atmospheric gas boiler, 1978 to 1994) ∆θgnr,test,P0 = 50 °C (Table B.2, atmospheric gas boiler, 1978 to 1994) 0,30 W 000 1 W 000 70 100 7,0 W 000 70 P0 ls, gnr, − | | . | \ | × × = = 1 370 W UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 80 Procedure step References Calculation details and results Calculation of corrected thermal losses at 0 % load 5.3.5.3 Table B.7 Eq. (18) θi,brm = 13 °C (Table B.7, in the boiler room) 1,25 corr P0, ls, gnr, C 50 C 13 C 67,8 W 370 1 | | . | \ | ° ° − ° × = = 1 535 W Calculation of corrected thermal losses at actual load 5.3.5.4 Eq. (21) Equation (21) because Px = H,gen,out > Pint W 810 5 W 409 4 W) 409 4 W 132 (11 kW 21 kW 70 kW 21 kW 31,2 Px ls, gnr, = + − × − − = Calculation of total generator thermal loss 5.3.5.4 Eq. (22) Qgnr,ls = 5,81 kW x 720 h = 4 183 kWh = 15 060 MJ Calculation of total generation thermal loss 5.3.5.5 Eq. (23) _ = ls gnr, ls gen, H, Q Q = 4 183 kWh = 15 060 MJ Calculation of auxiliary power at full load B.4 Table B.5 Eq. (B8) c7 = 40 W (Table B.5, boiler with atmospheric burner up to 250 kW) c8 = 0,148 W (Table B.5, boiler with atmospheric burner up to 250 kW) n = 1 (Table B.5, boiler with atmospheric burner up to 250 kW) 1 , 000 1 000 70 148 , 0 40 | | . | \ | × + = W W W W P Pn aux = 50 W Calculation of auxiliary power at intermediate load B.4 Table B.5 Eq. (B8) c7 = 40 W (Table B.5, boiler with atmospheric burner up to 250 kW) c8 = 0,148 W (Table B.5, boiler with atmospheric burner up to 250 kW) n = 1 (Table B.5, boiler with atmospheric burner up to 250 kW) 1 int , 000 1 000 21 148 , 0 40 | | . | \ | × + = W W W W P P aux = 43 W Calculation of auxiliary power at zero load B.4 Table B.5 Eq. (B8) c7 = 15 W (Table B.5, boiler with atmospheric burner up to 250 kW) c8 = 0 W (Table B.5, boiler with atmospheric burner up to 250 kW) n = 0 (Table B.5, boiler with atmospheric burner up to 250 kW) 0 0 , 000 1 000 21 0 15 | | . | \ | × + = W W W P P aux = 15 W Calculation of auxiliary power at actual load 5.3.6 Eq. (26) Equation (26) because gnr > int ( ) W W W P Px aux 43 50 30 , 0 1 30 , 0 446 , 0 43 , − × − − + = = 44,6 W Calculation of generator total auxiliary energy 5.3.6 Eq. (24) Wgnr,aux = 44,6 W x 720 h + 0 W x (720 h – 720 h) = 32,1 kWh Calculation of generation total auxiliary energy 5.3.6 Eq. (27) _ = aux gnr aux gen H W W , , , = 32,1 kWh = 115,7 MJ Calculation of generator recovered auxiliary energy 5.3.7.1 No recovered auxiliary energy is explicitly taken into account because it is already included in default data Qgnr,aux,rvd = 0 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 81 Procedure step References Calculation details and results Calculation of generator recoverable auxiliary energy (to the heated space) B.5.1 Eq. (B9) Table B.7 5.3.7.1 Eq. (29) frvd,aux = 0,75 frbl,aux = 1 – 0,75 = 0,25 bbrm = 0,3 (Table B.7, in the boiler room) Qgnr,aux,rbl = 32,1 kWh x (1 – 0,3) x 0,25 = 5,6 kWh = 20,2 MJ Calculation of generator thermal losses (generator envelope) 5.3.7.2 Table B.6 Eq. (30) fgnr,env = 0,50 (Table B.6, atmospheric burner) Qgnr,ls,env,rbl = 1 535 W x (1 – 0,3) x 0,50 x 720 h = 149,2 kWh = 537,2 MJ Calculation of total generation recovered auxiliary energy 5.3.7.3 Eq. (31) No recovered auxiliary energy is explicitly taken into account because it is already included in default data, hence QH,gen,aux,rvd = 0 Calculation of total generation recoverable thermal losses 5.3.7.3 Eq. (32) QH,gen,ls,rbl = 149,2 kWh + 5,6 kWh = 154,8 kWh = 557,4 MJ Calculation of total generation heat input 5.3.8 Eq. (1) EH,gen,in = 22 472 kWh – 0 kWh + 4 183 kWh = 26 656 kWh = 95 960 MJ F.2.3 Output data (connection to other parts of EN 15316) Table F.9 – Output data Description Symbol Value Fuel heat requirement EH,gen,in 26 656 kWh = 95 960 MJ Total generation thermal loss QH,gen,ls 4 183 kWh = 15 060 MJ Auxiliary energy WH,gen,aux 32,1 kWh = 115,7 MJ Recoverable thermal loss QH,gen,ls,rbl 154,8 kWh = 557,4 MJ UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 82 Annex G (informative) Calculation examples for boiler cycling method G.1 Modulating condensing boiler G.1.1 Input data Table G.1 – Boiler data Description Symbol References Value Boiler type Modulating condensing boiler Nominal power (heat input) cmb 74 kW Heat losses through the chimney with burner on (full load) ch,on 4 % Boiler return water temperature at test conditions for ch,on θgnr,w,r,test 60 °C Electrical power consumption of boiler auxiliaries at full load (before the burner) Pbr 210 W Electrical power consumption of boiler auxiliaries (after the burner) Ppmp 0 W (direct connection to distribution sub-system, no primary pump) Data from default tables Reference power ref 74 kW If not specified, it is assumed equal to cmb Correction factor for calculation of ch,on,corr fcorr,ch,on Table C.1 0,045 %/°C Condensing boiler Exponent for the load factor for calculation of ch,on,corr nch,on Table C.2 0,1 Steel boiler Heat losses through the boiler envelope ge Table C.3 Eq. (C1) High efficiency well insulated boiler | | . | \ | × − = W 000 1 W 000 74 log % 0,44 % 1,72 ge = 0,90 % Reduction factor of boiler envelope thermal losses kge,rvd Table C.4 0,7 Boiler located inside boiler room Exponent for the load factor for calculation of ge,corr nge Table C.5 0 Continuous circulation of water Heat losses through the chimney with the burner off ch,off Table C.6 0,2 % Boiler with automatic closure of air intake at burner off Exponent for the load factor for calculation of ch,off,corr nch,off Table C.7 0 Continuous circulation of water UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 83 Description Symbol References Value Temperature of test room for ge and ch,off θi,brm,test C.2.2 C.2.3 20 °C Boiler average water temperature at test conditions for ge and ch,off θgnr,w,m,test C.2.2 C.2.3 70 °C Recovery factor of Pbr kbr Table C.9 0,8 Default Recovery factor of Ppmp kpmp Table C.9 0,8 Default Additional data for modulating burner Minimum combustion power of the boiler cmb,min 18 kW Heat losses through the chimney with burner on (minimum load) ch,on,min 3 % Electrical power consumption of boiler auxiliaries at minimum combustion power Pbr,min 60 W Additional data for condensing boiler Temperature difference between boiler return water temperature and flue gas temperature (full load) wfg 25 °C Dry flue gas oxygen contents (full load) XO2 fg,dry 3 % Additional data from default tables for condensing boiler Combustion air relative humidity xair Table C.14 50 % Flue gas relative humidity xfg Table C.14 100 % Additional data for condensing multistage or modulating boiler Temperature difference between boiler return water temperature and flue gas temperature at minimum combustion power wfg,min 6 °C Flue gas oxygen contents at minimum combustion power XO2,fg,dry,min 4 % UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 84 Table G.2 – Data according to design or to other parts of this standard Description Symbol Value Operation time of the generator tgen 2 592 000 s = 720 h (*) Generator heat output QH,gen,out 80,9 GJ = 22 472 kWh Generation average temperature (**) θgen,f 48,9 °C Generation return temperature (**) θgen,r 37,7 °C Distribution flow rate V'dis 1 207 l/h Installation room temperature θi,brm 13 °C (default value for boiler room, Table C.4) Combustion air temperature θair 8 °C (monthly external average temperature) (*) Example estimated as 30 days, continuous operation. (**) Generation temperature is equal to average distribution. See calculation example in H.6. Table G.3 – Data according to fuel Description Symbol Value Fuel Natural gas (Groningen) Gross calorific value Hs 35 169 kJ/Nm³ Net calorific value Hi 31 652 kJ/Nm³ Stoichiometric dry air Vair,st,dry 8,4 Nm³/Nm³ Stoichiometric dry flue gas Vfg,st,dry 7,7 Nm³/Nm³ Stoichiometric water production mH2O,st 1,405 kg/Nm³ NOTE Data from Table C.13 G.1.2 Calculation procedure Table G.4 – Calculation procedure Procedure step References Calculation details and results Calculation of boiler average and return temperature H.2 Direct connection of the generator θgnr,w,m = θgen,m = 48,9 °C θgnr,w,r = θgen,r = 37,7 °C Selection of calculation procedure The boiler is modulating and is equipped with a condensing boiler, therefore the calculation procedure of 5.4.7 applies with extensions specified in 5.4.8. Calculation of cond,min (*) Calculate flue gas temperature 5.4.8.7 Eq. (74) θfg = 37,7 °C + 6 °C = 43,7 °C (wfg,min applied in eq. (74)) Calculate actual flue gas volume 5.4.8.7 Eq. (75) 4% 20,94% 20,94% m 7,7 3 dry fg, − ⋅ = N V = 9,52 Nm³ (XO2,fg,dry,min applied in eq. (75)) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 85 Procedure step References Calculation details and results Calculate actual combustion air 5.4.8.7 Eq. (76) Vair,dry = 8,4 m³ + 9,52 m³ – 7,7 m³ = 10,22 m³ Calculate air and flue gas saturation humidity 5.4.8.7 Table 3 mH2O,air,sat = 9,45 g/m³ with θair = 8 °C mH2O,fg,sat = 77,84 g/m³ with θfg = 43,7 °C Calculate combustion air absolute humidity 5.4.8.7 Eq. (77) 100% 50% 10,2m 9,45g/m 3 3 air H2O, × × = m = 48 g Calculate flue gas absolute humidity 5.4.8.7 Eq. (78) 100% 100% 9,52m 77,84g/m 3 3 fg H2O, × × = m = 741 g Condensate balance 5.4.8.7 Eq. (79) mH2O,cond,min = 1 405 g + 48 g – 741 g = 712 g Calculate specific latent heat of condensation 5.4.8.7 Eq. (80) hcond,fg,min = 2 500 600 J/kg – 43,7 °C x 2 435 J/kg·°C = 2,394 kJ/g Calculate actual latent heat of condensation 5.4.8.7 Eq. (81) Qcond,min = 712 g x 2,394 kJ/g = 1,71 MJ Calculate the condensation recovery factor 5.4.8.7 Eq. (83) MJ 31,6 MJ 1,71 100 min cond, × = = 5,39 % Try single stage procedure using minimum power output data Step 1 5.4.6 Single generator: QH,gen,out = 80,9 GJ Step 2 5.4.6 Operation time: tgen = 720 h Step 3 5.4.6 Set cmb = 1 Step 4 5.4.3 Eq. (40) Eq. (41) Eq. (44) ( ) [ ] 5,39% 1 C %/ 0,045 C 60 C 37,7 3% 0,1 cond min, on, ch, − × ° × ° − ° + = = - 3,39 0 corr ge, 1 C 20 C 70 C 13 C 48,9 0,7 % 0,9 × ° − ° ° − ° × × = = 0,45 % 0 corr off, ch, 1 C 20 C 70 C 13 C 48,9 % 0,2 × ° − ° ° − ° × = α = 0,14 % Step 5 5.4.5 Eq. (50) Eq. (52) Eq. (53) Qbr = 60 W x 0,80 x 720 h = 34,6 kWh Qpmp = 0 W x 0,80 x 720 h = 0 kWh WH,gen,aux = 34,6 kWh / 0,80 = 43,2 kWh Step 6 5.4.6 Eq. (54) ( ) 1,687 % 0,14 % 3,39 kW 74 kW 18 kW 74 kW 0,06 0,8 kW 18 % 100 % 0,45 % 0,14 kW 74 h 720 kWh 0 kWh 472 22 % 100 cmb = + − × − × + × + + × − × = β Step 7 5.4.6 After each iteration, the results are: cmb = 1,685 … 1,685 … 1,685 Since the final value is greater than 1, the burner is modulating between minimum and maximum power and cmb,avg has to be calculated according to the procedure in 5.4.7.3. Step 1 5.4.7.3 Single generator: QH,gen,out = 80,9 GJ Step 2 5.4.3 Eq. (41) ( ) ( ) 0 corr ge, 1 C 50 C 13 C 48,9 0,7 0,9% × ° ° − ° × × = α = 0,45 UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 86 Procedure step References Calculation details and results Step 3 5.4.3 Eq. (40) ( ) [ ] 0,1 corr min, on, ch, 1 C %/ 0,045 C 60 C 37,7 % 3 × ° × ° − ° + = α = 2 % ( ) [ ] 0,1 corr max, on, ch, 1 C %/ 0,045 C 60 C 37,7 4% × ° × ° − ° + = α = 3 % Step 4 5.4.5 Eq. (50) Qbr = 210 W x 0,80 x 720 h = 121 kWh Qbr,min = 60 W x 0,80 x 720 h = 34,6 kWh Step 5 5.4.7.3 cmb,avg = 74 kW Step 6a 5.4.7.3 Eq. (58) ( ) kW 18 kW 74 kW 18 kW 74 % 2 % 3 % 2 corr avg, on, ch, − − × − + = α = 3 % Step 6b 5.4.8.6 Eq. (72) ( ) kW 18 kW 74 kW 18 kW 74 C 6 C 25 C 6 avg wfg, − − × ° − ° + ° = ∆θ = 25 °C Step 6c 5.4.8.6 Eq. (73) ( ) kW 18 kW 74 kW 18 kW 74 % 4 % 3 % 4 avg dry, fg, O2, − − × − + = X = 3 % Step 6d 5.4.8.7 Calculation of cond using fg = 37,7 °C + 25 °C = 62,7 °C and XO2,fg,dry = 3 % yields: Vfg,dry = 8,99 m³ Vair,dry = 9,69 m³ mH2O,air,sat = 9,45 g/m³ with θair = 8 °C mH2O,fg,sat = 226,11 g/m³ with θfg = 62,7 °C mH2O,air = 46 g mH2O,fg = 2 032 g mH2O,cond = - 581 g cond,avg = 0 % because mH2O,cond < 0. Step 6e 5.4.8.6 Eq.(71) ch,on,avg,cond = 3 % - 0 % = 3 % Step 7 5.4.7.3 Eq. (59) ( ) kW 18 kW 74 kW 18 kW 74 kWh 34,6 kWh 121 kWh 34,6 avg br, − − × − + = Q = 121 kWh Step 8 5.4.7.3 Eq. (60) 100 % 3 1 kW 74 100 0,45 h 720 kWh 121 kWh 0 kWh 472 22 avg cmb, − × + − − = = 32,347 kW Step 9 5.4.7.3 Iterate againg from step 6 with cmb,avg = 32,347 kW Step 6a (2 nd iteration) 5.4.7.3 Eq. (58) ( ) kW 18 kW 74 kW 18 kW 32,35 % 2 % 3 % 2 corr avg, on, ch, − − × − + = α = 2,26 % Step 6b (2 nd iteration) 5.4.8.6 Eq. (72) ( ) kW 18 kW 74 kW 18 kW 32,35 C 6 C 25 C 6 avg wfg, − − × ° − ° + ° = ∆θ = 10,9 °C Step 6c (2 nd iteration) 5.4.8.6 Eq. (73) ( ) kW 18 kW 74 kW 18 kW 32,35 % 4 % 3 % 4 avg dry, fg, O2, − − × − + = X = 3,74 % UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 87 Procedure step References Calculation details and results Step 6d (2 nd iteration) 5.4.8.7 Calculation of cond using fg = 37,7 °C + 10,9 °C = 48,6 °C and XO2,fg,dry = 3,74 % yields Vfg,dry = 9,38 m³ Vair,dry = 10,08 m³ mH2O,air,sat = 9,45 g/m³ with θair = 8 °C mH2O,fg,sat = 103,98 g/m³ with θfg = 48,6 °C mH2O,air = 48 g mH2O,fg = 975 g mH2O,cond = 478 g hcond,fg = 2,382 kJ/g cond,avg = 3,59 % Step 6e (2 nd iteration) 5.4.8.6 Eq. (71) ch,on,avg,cond = 2,26 % - 3,59 % = - 1,34 % Step 7 (2 nd iteration) 5.4.7.3 Eq. (59) ( ) kW 18 kW 74 kW 18 kW 32,35 kWh 34,6 kWh 121 kWh 34,6 avg br, − − × − + = Q = 56,74 kWh Step 8 (2 nd iteration) 5.4.7.3 Eq. (60) 100 % 1,34 1 kW 74 100 0,45 h 720 kWh 56,7 kWh 0 kWh 472 22 avg cmb, − − × + − − = = 31,05 kW Step 9 (further iterations) 5.4.7.3 Iterations starting again from step 6 yield the following values for cmb,avg: 30,991 kW … 30,988 kW and converges to 30,988 kW Step 10 5.4.7.3 Eq. (61) EH,gen,in = 30,988 kW x 720 h = 22 311 kWh = 80 321 MJ Step 11 5.4.7.3 Eq. (62) ( ) kW 18 kW 74 kW 18 kW 30,988 W 60 W 210 W 60 avg br, − − × − + = = 94,8 W Step 12 5.4.7.3 Eq. (63) WH,gen,aux = 720 h x (94,8 W + 0 W) = 68,2 kWh Step 13 5.4.7.3 Eq. (64) WH,gen,aux,rvd = 720 h x (94,8 W x 0,8 + 0 W x 0,8) = 54,6 kWh = 197 MJ Step 14 5.4.7.3 Eq. (65) QH,gen,ls = 22 311 kWh – 22 472 kWh + 55 kWh = - 106 kWh = - 382 MJ (*) Calculation referred to the unit mass of fuel (Nm³ in this example). NOTE All iterations shown converge in 2 or 3 runs. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 88 G.1.3 Output data (connection to other parts of EN 15316) Table G.5 – Output data Description Symbol Value Fuel heat requirement EH,gen,in 22 311 kWh = 80 321 MJ Total generation thermal loss QH,gen,ls - 106 kWh = - 382 MJ Auxiliary energy WH,gen,aux 68,2 kWh Recoverable thermal loss QH,gen,ls,rbl 0 kWh = 0 MJ G.2 Standard, on-off atmospheric boiler G.2.1 Input data Table G.6 – Boiler data Description Symbol References Value Boiler type Single stage atmospheric boiler Nominal power (heat input) cmb 74 kW Boiler average water temperature at test conditions for ch,on θgnr,w,m,test 70 °C Data from default tables Reference power ref 5.4.2 74 kW If not specified, it is assumed equal to cmb Heat losses through the chimney with burner on (full load) ch,on Table C.1 12 % Atmospheric boiler Correction factor for calculation of ch,on,corr fcorr,ch,on Table C.1 0,045 %/°C Atmospheric boiler Exponent for the load factor for calculation of ch,on,corr nch,on Table C.2 0,15 Cast iron boiler Heat losses through the boiler envelope ge Table C.3 Eq. (C1) Old boiler with average insulation | | . | \ | × − = W 000 1 W 000 74 log % 1,76 % 6,79 ge α = 3,61 % Reduction factor of boiler envelope thermal losses kge,rvd Table C.4 0,7 Boiler located inside boiler room Exponent for the load factor for calculation of ge,corr nge Table C.5 0 Continuous circulation of water Heat losses through the chimney with the burner off ch,off Table C.6 1,6 % Atmospheric gas fired boiler, chimney height > 10 m UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 89 Description Symbol References Value Exponent for the load factor for calculation of ch,off,corr nch,off Table C.7 0 Continuous circulation of water Temperature of test room for ge and ch,off θi,brm,test C.2.2 C.2.3 20 °C Boiler average water temperature at test conditions for ge and ch,off θgnr,w,m,test C.2.2 C.2.3 70 °C Auxiliary power before the combustion chamber Pbr C.3 Table C.8 Eq. (C2) c3 = 40 W (atmospheric burner) c4 = 0,148 W (atmospheric burner) n = 1 (atmospheric burner) 1 br W 000 1 W 000 74 W 0,148 W 40 | | . | \ | × + = P = 51 W Auxiliary power after the combustion chamber Ppmp C.3 Table C.8 Eq. (C2) c3 = 100 W (all boilers) c4 = 2 W (all boilers) n = 1 (all boilers) 1 pmp W 000 1 W 000 74 W 2 W 100 | | . | \ | × + = P = 248 W Recovery factor of Pbr kbr Table C.9 0,8 Default Recovery factor of Ppmp kpmp Table C.9 0,8 Default Table G.7 – Data according to design or to other parts of this standard Description Symbol Value Operation time of the generator tgen 2 592 000 s = 720 h (*) Generator heat output QH,gen,out 80,9 GJ = 22 472 kWh Generation average temperature (**) θgen,f 48,9 °C Generation return temperature (**) θgen,r 37,7 °C Distribution flow rate V'dis 1 207 l/h Installation room temperature θi,brm 13 °C (default value for boiler room, Table C.4) (*) Example estimated as 30 days, continuous operation. (**) Generation temperature is equal to average distribution. See calculation example in H.6. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 90 G.2.2 Calculation procedure Table G.8 – Calculation procedure Procedure step References Calculation details and results Calculation of generation average power s 000 592 2 GJ 80,9 out gen, H, = = 31,2 kW Calculation of boiler flow, return and average temperature H.3 Eq. (H4) Eq. (H5) H.5 Eq. (H11) Independent flow rate. Generation flow rate is higher than distribution flow rate θgnr,w,f = 70 °C (design and set value) θgnr,w,r = m³/s 10 1,67 C J/kg 186 4 kg/m³ 1000 W 200 31 C 70 3 − × × ° ⋅ × − ° = 65,5 °C θgnr,w,m = 2 C 65,5 C 70 ° + ° = 67,8 °C Single stage procedure according to 5.4.6 Step 1 5.4.6 Single generator: QH,gen,out = 80,9 GJ Step 2 5.4.6 Operation time: tgen = 720 h Step 3 5.4.6 Set cmb = 1 Step 4 5.4.3 Eq. (40) Eq. (41) Eq. (44) ( ) [ ] 0,15 corr on, ch, 1 C %/ 0,045 C 67,8 C 70 12% × ° × ° − ° + = α = 11,9 % 0 corr ge, 1 C 20 C 70 C 13 C 67,8 0,7 % 3,61 × ° − ° ° − ° × × = α = 2,77 % 0 corr ch.off, 1 C 20 C 70 C 13 C 67,8 % ,6 1 × ° − ° ° − ° × = α = 1,75 % Step 5 5.4.5 Eq. (50) Eq. (52) Eq. (53) Qbr = 51 W x 0,80 x 720 h x 1 = 29,4 kWh Qpmp = 248 W x 0,80 x 720 h = 142,8 kWh WH,gen,aux = 29,4 kWh / 0,8 + 142,8 kWh / 0,8 = 215 kWh Step 6 5.4.6 Eq. (54) % 1,75 % 11,9 kW 74 kW 74 kW 74 kW 0,051 0,8 kW 74 % 100 % 2,77 % 1,75 kW 74 h 720 kWh 142,8 kWh 472 22 % 100 cmb + × − × + × + + × − × = β = 0,516 Step 7 5.4.6 Iterate again from step 4 with cmb = 0,516 Step 4 (2 nd iteration) 5.4.3 Eq. (40) Eq. (41) Eq. (44) ( ) [ ] 0,15 corr on, ch, 0,516 C %/ 0,045 C 67,8 C 70 12% × ° × ° − ° + = α = 10,8 % 0 corr ge, 0,516 C 20 C 70 C 13 C 67,8 0,7 % 3,61 × ° − ° ° − ° × × = α = 2,77 % 0 corr off, ch, 0,516 C 20 C 70 C 13 C 67,8 % 1,6 × ° − ° ° − ° × = α = 1,75 % Step 5 (2 nd iteration) 5.4.5 Eq. (50) Eq. (52) Eq. (53) Qbr = 51 W x 0,80 x 720 h x 0,516 = 15,2 kWh Qpmp = 248 W x 0,80 x 720 h = 142,8 kWh WH,gen,aux = 15,2 kWh / 0,8 + 142,8 kWh / 0,8 = 197,5 kWh UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 91 Procedure step References Calculation details and results Step 6 (2 nd iteration) 5.4.6 Eq. (54) % 1,75 % 10,8 kW 74 kW 74 kW 74 kW 0,051 0,8 kW 74 % 100 % 2,77 % 1,75 kW 74 h 720 kWh 142,8 kWh 472 22 % 100 cmb + × − × + × + + × − × = β = 0,510 Step 7 (further iterations) 5.4.6 After each iteration, further results are: cmb = 0,510 … 0,510 … 0,510 and cmb converges to 0,510 (WH,gen,aux converges to197,3 kWh) Step 8 5.4.6 Eq. (55) EH,gen,in = 74 kW x 720 h x 0,51 = 27 169 kWh = 97 808 MJ Step 9 5.4.6 Eq. (56) QH,gen,ls = 27 169 kWh – 22 472 kWh + 15 kWh + 143 kWh = 4 855 kWh = 17 478 MJ NOTE All iterations shown converge in 2 or 3 runs. G.2.3 Output data (connection to other parts of EN 15316) Table G.9 – Output data Description Symbol Value Fuel heat requirement EH,gen,in 27 169 kWh = 97 808 MJ Total generation thermal loss QH,gen,ls 4 855 kWh = 17 478 MJ Auxiliary energy WH,gen,aux 197,3 kWh Recoverable thermal loss QH,gen,ls,rbl 0 kWh = 0 MJ UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 92 Annex H (informative) Boiler water temperature calculation H.1 Boiler flow temperature and return temperature The following data:  θ gnr,w,m average water temperature in the boiler;  θ gnr,w,r average return water temperature to the boiler; are required to correct heat loss coefficients and calculate condensate production according to actual operation conditions. Calculation of flow rates is not fully detailed in this standard. Any design flow rate value shall be calculated separately with appropriate methods. Calculation is performed starting with the emission sub-system and taking into account the hydraulic design or the actual hydraulic layout as well as the operation of the heating system. Subsequently, the effect of the type of generation circuit is taken into account. A generation circuit may include mixing, recirculation or buffer connections. Therefore, generation circuit flow rate and temperatures may differ from boiler flow rate and temperatures. In this annex, the following indices are applied:  gnr for boiler values (generator);  gen for generation circuit values. An example of a generation circuit is shown in Figure H1. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 93 Figure H1 - Sample generation circuit Key GNR generator (boiler) PMP primary pump BV balancing valve θgen,f generation circuit flow temperature, which is also the distribution flow temperature θdis,f θgen,r generation circuit return temperature, which is also the distribution return temperature θdis,r V'gen generation circuit flow rate, which is also the distribution flow rate V'dis ΦH,gen,out heat power output of the generation circuit V'gnr boiler flow rate θgnr,w,f boiler flow temperature θgnr,w,r boiler return temperature θgnr,w,m boiler average water temperature H.2 Boiler flow rate is the same as the distribution flow rate (no by-pass) If the boiler flow rate V' gnr is the same as the generation circuit flow rate V' gen , then f gen, f w, gnr, = θ (H1) r gen, r w, gnr, = θ (H2) gen gnr ' ' V V = (H3) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 94 Examples of such circuits are given in Figure H2. NOTE Flow in the buffer is controlled and not allowed to cool or heat completely. Key GNR generator (boiler) PMP primary pump BV balancing valve BUF buffer Figure H2 - Boiler flow rate is the same as generation circuit flow rate H.3 Boiler flow rate is not the same as the distribution flow rate (by-pass connection or recirculation pump) If the boiler flow rate V' gnr is greater than the generation circuit flow rate V' gnr (V' gnr > V' gen ), then: f gen, f w, gnr, θ θ = (H4) gnr w w out gnr, f w, gen, r w, gnr, ' V c ⋅ ⋅ − = θ (H5) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 95 where w density of water; c w specific heat of water; gnr,out boiler heat output. NOTE θgnr,w,r is higher than θgen,w,r. If the boiler flow rate V' gen is less than the generation circuit flow rate V' gen (V' gnr < V' gen ), then: r gen, r w, gnr, θ θ = (H6) gnr w w out gnr, r w, gen, f w, gnr, ' V c ⋅ ⋅ + = θ (H7) NOTE θgnr,f is higher than θgen,f. θ gnr,w,r and θ gnr,w,f are in any case given by: ( ( ¸ ( ¸ ⋅ ⋅ − = gnr w w out gnr, f w, gen, r gen, r w, gnr, ; max V' c θ (H8) ( ( ¸ ( ¸ ⋅ ⋅ + = gnr w w out gnr, r w, gen, f gen, f w, gnr, ' ; max V c θ (H9) which combine equations (H4) to (H7). Examples of such circuits are given in Figure H3. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 96 Key GNR generator (boiler) PMP primary pump BV balancing valve BUF buffer Figure H3 – Boiler flow rate is not the same as generation circuit flow rate NOTE 1 The flow rate V’gnr through the boiler is the average flow rate. Using a buffer allows low flow rate operation of the generation circuit through intermittent operation of the boiler pump. NOTE 2 Some old systems incorporate a condensate prevention pump. Its flow rate adds to the generation circuit flow rate to give the boiler flow rate. H.4 Parallel connection of boilers If more boilers are connected in parallel, the common return temperature θ gnr,r and the resulting flow temperature θ gnr,f are calculated according to H.3 using the total flow rate and the total heat output. The average heat power output Φ gnr,out,i and flow rate V' gnr,i of each boiler have to be determined. UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 97 Then the flow temperature θ gnr,w,f,i of each boiler i is calculated with: i gnr, w w i out, gnr, r w, gnr, i f, w, gnr, ' V c ⋅ ⋅ + = θ (H10) An example of a parallel connection is given in Figure H4. Key GNR1, GNR2 generators (boilers) PMP1, PMP2 primary pumps BV balancing valve Figure H4 - Parallel connection of boilers H.5 Boiler average water temperature The boiler average water temperature θ gnr,w,m is given by: 2 r w, gnr, f w, gnr, m w, gnr, + = θ (H11) UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 98 H.6 Example of water temperature calculation Table H.1 – Input data Description Symbol References Value Distribution sub-system output QH,dis,out EN15316-2-3 75 125 MJ = 20 868 kWh Distribution sub-system input QH,dis,in EN15316-2-3 80 900 MJ = 22 472 kWh Type of heat emitters radiators Nominal power of installed heat emitters emr,n 70 000 W Design temperature difference between emitters and room temperature em,des 50 °C Exponent of the emitters nemr 1,3 Internal temperature of heated space i 20 °C Calculation period tci 720 h Operation time of distribution tdis 720 h (continuous operation) Type of heat emitter control Thermostatic valves Set emitters flow temperature emr,f 53 °C Type of distribution circuit Mixing valve Set distribution flow temperature dis,f 60 °C Table H.2 – Calculation procedure Procedure step References Calculation details and results Emitters temperature calculation according to EN 15316-2-3:2007, Clauses 7 and 8.1. Emitters load EN 15316-2-3 Eq. (38) h 720 kW 70 kWh 472 22 dis × = β = 0,414 Calculation of the emitters average temperature EN 15316-2-3 Eq. (43) emr,m = 20 °C + 50 °C x 0,414 1/1,3 = 45,4 °C Calculation of the emitters return temperature EN 15316-2-3 Eq. (45) emr,r = max (2 x 45,4 °C – 53 °C; 2 °C) = 37,7 °C Distribution circuit temperature calculation according to EN 15316-2-3:2007, Clause 8.3. Distribution circuit flow temperature dis,f = 60 °C (set value) Distribution circuit return temperature EN 15316-2-3 Eq. (49) dis,r = 37,7 °C (the same as emitters flow temperature) Distribution input power dis,in = 22 472 kWh/720 h = 31,21 kW Distribution circuit flow rate EN 15316-2-3 Eq. (50) ( ) C 37,7 C 60 C J/kg 4186 kg/m³ 1000 W 211 31 . ° − ° × ° ⋅ × = dis V = 0,33 kg/s = 1 207 kg/h UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) EN 15316-4-1:2008 (E) 99 Bibliography [1] Council Directive 92/42/EEC of 21 May 1992 about the efficiency requirements of the new gas or oil boilers [2] EN 15316-1, Heating systems in buildings - Method for calculation of system energy requirements and system efficiencies – Part 1: General [3] EN 15316-3-3, Heating systems in buildings - Method for calculation of system energy requirements and system efficiencies – Part 3.3: Domestic hot water systems, generation [4] EN ISO 9488, Solar energy – Vocabulary (ISO 9488:1999) [5] ISO 13602-2, Technical energy systems – Methods for analysis – Part 2: Weighting and aggregation of energywares UNI EN 15316-4-1:2008 Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...) Riproduzione vietata - Legge 22 aprile 1941 Nº 633 e successivi aggiornamenti. UNI Ente Nazionale Italiano di Unificazione Via Sannio, 2 20137 Milano, Italia Licenza d'uso concessa a UNI VERSI TA' CENTRO ATENEO DOC.P OLO MONTE DAGO per l'abbonamento anno 2008. Licenza d'uso interno su postazione singola. Riproduzione vietata. E' proibito qualsiasi utilizzo in rete (LAN, internet, etc...)